text:
Why does negative life and Platinum Angel not cause a draw?
I was looking at the Transcendence, Platinum Angel interaction. As it is explained in a few places online

Transcendence has what is called a 'State Trigger'. It triggers
  whenever the condition is met provided there isn't a copy of that
  trigger on the stack already.  What will happen is Transcendence will
  continue to trigger over and over again since you don't lose the game
  due to Platinum Angel. There is no way to stop this without a player
  doing something and that is not required so the game ends in a draw.

But why does this not happen if the player reaches negative life? I know from playing MTGO a player can continue playing the game with negative life if the Platinum Angel is in play.

119.6. If a player has 0 or less life, that player loses the game as a state-based action. See rule 704.

What prevents the death trigger from firing over and over similar to Transcendence? When is loss checked if Platinum Angel leaves the field if it's not done continuously?

The normal loss condition of having zero or less life happens only once per check of state-based actions. The Transcendence loss ability triggers continuously in an infinite loop, with no way to continue playing.
The loss to zero or less life happens due to state-based actions. They are checked often, but not infinitely often. They are checked whenever a player would gain priority, which happens only at specific points during any given turn.

117.3a The active player receives priority at the beginning of most steps and phases, after any turn-based actions (such as drawing a card during the draw step; see rule 703) have been dealt with and abilities that trigger at the beginning of that phase or step have been put on the stack. No player receives priority during the untap step. Players usually don’t get priority during the cleanup step (see rule 514.3).
117.3b The active player receives priority after a spell or ability (other than a mana ability) resolves.
117.3c If a player has priority when they cast a spell, activate an ability, or take a special action, that player receives priority afterward.
117.3d If a player has priority and chooses not to take any actions, that player passes. If any mana is in that player’s mana pool, they announce what mana is there. Then the next player in turn order receives priority.
117.5. Each time a player would get priority, the game first performs all applicable state-based actions as a single event [..]

Platinum Angel prevents that single loss event each time a player would gain priority, and that's that.
The loss ability of Transcendence, however, has a state trigger. It will trigger whenever the game state in question has been reached and no instance of that ability is currently on the stack. As soon as the trigger leaves the stack (or doesn't enter it) for any reason, and the game is still in the necessary state, the ability will trigger again right away, without anyone being able to react. Platinum Angel's ability removes the Transcendence trigger from the stack by preventing it. The Transcendence ability never enters the stack, it immediately triggers again, and no player will gain priority, resulting in a draw.

603.8. Some triggered abilities trigger when a game state (such as a player controlling no permanents of a particular card type) is true, rather than triggering when an event occurs. These abilities trigger as soon as the game state matches the condition. They’ll go onto the stack at the next available opportunity. These are called state triggers. (Note that state triggers aren’t the same as state-based actions.) A state-triggered ability doesn’t trigger again until the ability has resolved, has been countered, or has otherwise left the stack. Then, if the object with the ability is still in the same zone and the game state still matches its trigger condition, the ability will trigger again.
614.6. If an event is replaced, it never happens. [..]
603.3. Once an ability has triggered, its controller puts it on the stack as an object that’s not a card the next time a player would receive priority.

So what happens is, Transcendence triggers. The next time a player would gain priority, the Transcendence trigger wants to enter the stack, but Platinum Angel prevents that. Transcendence immediately triggers again, Platinum Angel prevents it again, and so on, before the player can ever gain priority. Therefore, it's a draw because there is a loop with only mandatory actions.

721.4. If a loop contains only mandatory actions, the game is a draw.

“The Transcendence ability never enters the stack” — this is false. It is put on the stack, then players get priority as usual, then it resolves, however, the angel causes it not to have any effect. Any player, if they wish, can use the priority to cast a removal spell on the angel or do something else. Only if no-one removes the angel, the loop results in a draw.

What is this, a badly written computer program? If the trigger doesn't advance state, it can be shortcutted out.

In addition to Hacksworth's good answer, here are details on the way that state-based actions are checked:

704.3. Whenever a player would get priority (see rule 117, “Timing and Priority”), the game checks for any of the listed conditions for state-based actions, then performs all applicable state-based actions simultaneously as a single event. If any state-based actions are performed as a result of a check, the check is repeated; otherwise all triggered abilities that are waiting to be put on the stack are put on the stack, then the check is repeated. Once no more state-based actions have been performed as the result of a check and no triggered abilities are waiting to be put on the stack, the appropriate player gets priority. This process also occurs during the cleanup step (see rule 514), except that if no state-based actions are performed as the result of the step’s first check and no triggered abilities are waiting to be put on the stack, then no player gets priority and the step ends.

And the first state-based action:

704.5. The state-based actions are as follows:
  704.5a If a player has 0 or less life, that player loses the game.

So the state-based action checks are repeated, but only if an action actually happened as a result of the check. Because Platinum Angel prevents 704.5a from actually happening, then there is no action that happened (assuming no other applicable actions happened at the same time), and so the check is not repeated. They will be checked again next time a player is about to receive priority, but not until then.


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Why was Gifts Ungiven so popular?
Back in Kamigawa Block, Gifts Ungiven was a very popular card, showing up in a good percentage of blue decks.  I don't understand why it's considered useful.  What made this card so popular?

I'm sorry, you don't think that a Diabolic Tutor in blue (for the same cost) that tutors two cards instead of one (giving you card advantage), can be cast at instant speed (on your opponents turn with untapped mana that's a counterspell threat), and puts two cards in your graveyard is useful?
The only drawback is that the opponent gets to choose which two cards you tutor out of four possibilities. If they are all four good, useable cards, (which they naturally should be if you have crafted a good deck) this is hardly a drawback.
Many decks ran this with Psychatog, as those two cards in the graveyard and those two cards in your hand, if nothing else, help power the 'tog.
I've seen other decks run this with "return creature card from graveyard" spells. Gifts up two of these spells and two big beaters. What does the opponent do?
I found this article on Star City Games showing the sort of broken things you could do with Gifts in Kamigawa block.
Also, consider Careful Consideration

Target player draws four cards, then discards three cards. If you cast this spell during your main phase, instead that player draws four cards, then discards two cards.

It costs the same (one blue mana instead of one colourless), doesn't let you choose which four cards to draw, and you only get to discard two cards if you cast it in your main phase.
Gifts Ungiven is a very undercosted powerful card with the potential to be broken.

You also have the option of only finding 2 cards and in that case they both go to the graveyard.

@Matt, Or search for three cards and force your opponent to give you one; if they're all functionally similar (or identical), or two are recursion cards, there is no winning choice for the opponent. Similarly with two, you can get a recursion card with Flashback (Dread Return, Unburial Rites, etc.) and a target for recursion.

The short version
Gifts Ungiven was — and is — popular because it's one of the most powerful and flexible tutor cards in Magic, thanks to its ability to find multiple relevant cards for just 4 mana, at instant speed. In practice, the card is much more powerful than it looks:

The opponent's choice is not a meaningful disadvantage: it's easy to render the opponent's choice practically meaningless, using functional equivalents or Regrowth effects.
Putting cards in your graveyard is actually a desirable feature of the card, not a disadvantage: it's fairly easy to build decks that efficiently reuse cards in your graveyard; it's very easy to cheat on costs when you do that, too.
Tutoring for multiple cards is super-powerful: Gifts is exceptionally good at setting up combos and engines.

The long version
Gifts Ungiven isn't just any tutor card. Sure, it costs the same as Diabolic Tutor, with the following added bonuses:

Gifts is an instant-speed tutor in blue, the best "draw-go" color. You don't have to tap out on your own turn to cast Gifts. Instead, you can keep your mana open, ready to counter any important plays your opponent makes, and then play Gifts whenever it's convenient.
Gifts gives you more than one card. That's always good, right?

So, it's at least as good as Mystical Teachings (also an instant-speed tutor with built-in card advantage — one that saw tournament play during Time Spiral Standard and later in Modern). But it's way better than that, too!
Gifts give you four cards. Not two cards, four cards — it's just that two of them will end up in your graveyard. And you get all those cards at the same time, which makes it an amazing combo tutor.
Your opponent gets to control which cards go where, but, with careful deck-building and skillful play, you can get much more power from the card by effectively removing your opponent's meaningful choices.
Functional equivalents
At the least, Gifts allows you to tutor for four cards and get the third and fourth best ones for the current situation into your hand. That's pretty powerful by itself, though it relies on building a deck that even has a third and fourth best card for many situations.
An easy way to get that effect is to run one-ofs of a bunch of very similar cards, so that your "third best" card is basically the same as your "best" card. Here's the classic example:
(I'm using general examples rather than all Kamigawa-block ones because it's much easier to think about what's good in general Magic than in the rather idiosyncratic world of any set's Block Constructed.)

Two of those cards will end up in your hand. Three of them are 4-drop sweepers. So, whatever your opponent picks, you're guaranteed at least one sweeper in your hand. (The fourth card could be anything, in this case — Path to Exile just fits because you can use it to answer a creature your opponent plays after the wrath.)
Regrowth effects
Running lots of functional equivalents takes up a lot of space in your deck. This isn't too bad for the sweepers example above, since decks often run three of four wraths anyway. When you've got one particular, functionally-unique card you really want, though, or a niche case where you'd only run a one-of.
A common solution is to run "Regrowth" effects, forcing your opponent to choose between the card you want and a card that'll fish it out of your graveyard.
An example from the Kamigawa era is Frank Karsten's 2005 Worlds (Standard) deck. Let's say Frank's opponent has an artifact that needs to be removed right away. The deck has one maindeck answer — Putrefy. Here's a way he could tutor it with Gifts:

Recollect gives you Putrefy back in hand. Reclaim can put it on top of your library; you could either cast Reclaim on your upkeep and draw the card naturally, or use the Top to bring the card to your hand. Your opponent can make you spend a couple of cards and some extra mana to cast Putrefy, but, short of graveyard hate, he can't keep you from casting it.
An easy way to get the same effect with more recent cards, without even having to run green mana sources, is to include Snapcaster Mage and Noxious Revival in your Gifts pile.
Card you just want in your graveyard anyway
Hopefully you saw that this is where we were going when I mentioned Snapcaster.
The graveyard is a very active zone in Magic. So much so that some cards are actually at their most powerful in the 'yard. Kenji Tsumura's 2005 Pro Tour Los Angeles (Extended) deck includes Darkblast and Life from the Loam, whose Dredge ability helps power up his Psychatogs; as well as Wonder, whose in-your-graveyard ability is more relevant than the creature itself.
Flashback cards are great to tutor up with Gifts — whether they go in your hand or the graveyard, you can cast 'em either way. In addition, it's important to note that this is a valid Gifts pile:

That's it! Just two cards.

701.14b If a player is searching a hidden zone for cards with a stated quality, such as a card with a    certain card type or color, that
  player isn’t required to find some or all of those cards even if
  they’re present in that zone.

(The "stated quality" in this case is "different names".)
Since your opponent must choose two cards to go in your graveyard, both of these will end up in your 'yard. At which point you can flashback Rites and bring out your big reanimated finisher. It's the best graveyard-filling tutor this side of Entomb!
I believe the first example of using Gifts like this was actually during Kamigawa block. During one of the Pro Tour matches, a player was about to lose the game but had Goryo's Vengeance and Gifts in hand. So he Gifts-ed for just Kokusho and then let him die to drain his opponent.
Combos and engines
You know how Tooth and Nail is so good because you can dig out both pieces of a combo at the same time?
Gifts does that as well. It's especially easy with graveyard-based engines. For example, Patrick Chapins' 2008 Pro Tour Berlin (Extended) deck could set up his win condition using something like this:

Regardless of which card goes where, this sets up an engine that lets you make a bunch of Worm tokens every turn.
Plain old deception
Setting up "no-win scenarios" for your opponent is powerful and consistent, but sometimes you don't even need to do that.
For instance, let's say you have Urza's Mine, Urza's Tower, Steam Vents, and two Izzet Signets in play (five mana total, but one land away from completing the UrzaTron).
You show me this Gifts pile:

Now, I do have real, serious choices here.

If I let you complete your Tron with the Power Plant, you might cast something nasty next turn — or have nothing to do with all your mana.
If I give you Through the Breach, you could crush me with an Eldrazi next turn, but only if you have one in hand.
If I give you Emrakul, it might sit uselessly in your hand for a number of turns. Or you might be sanbagging a Power Plant already in hand, ready to ramp you all the way to 15 mana in a couple more turns.

There are right choices and wrong choices, but they're based on hidden information. If I guess wrong, you're probably won the game. You're taking a chance when you do this, of course, but it's a chance with a big upside.
Another common way to play mind games with your opponent is to use the Regrowth trick detailed above, but then regrow some other card that was already sitting innocuously in your graveyard.
What a truly busted Gifts deck looks like
Did you know that Gifts Ungiven is restricted in Vintage and banned in Commander? Do you ever wonder why?
Look at this deck (more discussion available here).

Gifts gets so much better with a deeper card pool: there are more ways to cast stuff from your graveyard, more functional equivalents to choose from, more powerhouse "silver bullet" singletons, more two-card combos.
In the right deck, Gifts Ungiven is a one-card combo, an obscene card advantage engine, and every kind of disruption you need to win the game.

To add to ghoppe's answer: Over the past years, MtG has become a very mature game. In particular, library and graveyard manipulation have become very popular, getting a lot of love by the designers, and many mechanics as well as cards now involve these zones.
Considering this, Gifts Ungiven is a very powerful card that, if you design your deck right, actually gives you up to four cards of your choice, two of them into your hand, and three (including Gifts) into your graveyard. Since it's an instant, you can play it at the end of your opponent's turn, which further increases its versatility.

Consider you fetch for: Academy Ruins, Life from the Loam, Wasteland and Crucible of Worlds.
Whatever cards your opponent chooses you'll get all parts to your soft lock. This is just an example, I'm sure there are a lot better card combinations to fetch for. Keep in mind this is for the reasonable cost of 4 mana instant.

source: Stack Exchange

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"The Terrible Experiment" Mythos Card - How to deal with it?
Yesterday my game was progressing quite smoothly until we got "The Terrible Experiment" Mythos card.
http://www.arkhamhorrorwiki.com/The_Terrible_Experiment
We were playing with two investigators and immediately tried to go to the Miskatonic University and try to fight the monsters off but some were just too powerful to deal with.
One of the investigators ended up in the hospital and after a while we realized it might have just been better to let the monsters pile up on the card and to have the terror level raised to 10 and all those monsters on the board instead of trying to fight them off.
What are some strategies to deal with this card?

I definitely don't think this is opinion based; I have re-worded the last sentence to remove the appearance of an opinion-based question.

Player count is going to have a pretty big effect on how to deal with the card, 2 players is going to be tough, but with 4 or 5 it becomes easier. Strategies might help, but some of the cards are just plain unbalanced at lower player counts.

The first time we encountered this rumor, we used Flute of the Elder Gods on it.  On reread, I suspect we were cheating but if you don't agree then that might be a strategy...which could be generalized as try and buy stuff to help (you do have a couple turns to prepare right after the rumor appears).
Note, the rumor also says "one or more monsters".  In subsequent runs I've definitely cherry picked the easy ones and let it build up again.  This is somewhat luck based and won't help you if they're all harder than you can defeat.  Similar to the above comments and other answer, if you have no-one who can fight at all, it is probably better to push on, so is dependant on the variables of the game (which make the game replay value skyrocket IMO=)).
I guess along with the above strategy if you have a bunch of easy monsters as trophies might be worth spending them to get them back in the pool.
It may also be noteworthy to newer players that the positioning of this rumor is between Hospital and Asylum so if you have a lot of money isn't a terrible position to recharge in between fights (well one stat anyway).  This is dependant upon how clean your streets are/your sneak, another variable :D
Really this answer and likely any answer could be applied to fighting in general.  The rumor just adds a terrible downside if you fail.

There are a lot of variables you need to consider before fighting any monster.

Number of players vs Number of Monsters
Number of items player(s) have collected to help them in the fight
How tough are/is the monster(s) being fought? Stats are public knowledge.
Does the player characters have any stats or character traits that help them better fight or longer sustain the monster?
How far in the game is this?
How close are you to losing?
What is the worst that can happen if we do not fight the monster(s)?

Maybe this is the end card for your game. Neither option is good. These Arkham/Eldritch games can/are difficult games. It can be brutal. Maybe your team has gotten lucky though. Found good items or started with characters that are good fighting monsters. Maybe it's an easy card to just push through and be done with.
In the end, with all things in the current game considered, it comes down to:"Do we as a team think it's better to fight or is it more efficient to push to the win?"

It says you may fight one or more monsters on the card from Miskatonic U, so you don't need to clear it immediately, you can just keep it in check with one player defeating monsters while the other one builds themselves up and finds items with the goal of beating the stronger ones. This will make the overall game harder since it effectively removes one of the players, but this is already going to be a very hard game with only two players.

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How do you score an all wild card Canasta?
Today I made my first ALL Wild card Canasta with six 2's and a Joker in Classic Canasta :O)
How much is this worth please?
Also, it was concealed... does that 'Up' the bonus?

Are you playing classic Canasta or modern/American Canasta?

Hiya, We are playing Classic here in Surrey in the UK.

In Classic Canasta, a Canasta of only wilds is not a legal/valid meld.
From the rules:

Every meld, whether a Canasta or not, must contain at least 2 natural cards, and it cannot contain more than 3 total wild cards.
Every meld must contain at least two natural cards. The smallest meld, as usual, consists of three cards, which could be three natural cards (such as 8-8-8) or two natural cards and a wild card (such as Q-Q-2).
Melds can grow as large as you wish. A meld of seven or more cards counts as a canasta. No meld can contain more than three wild cards - so a six card meld must include at least three natural cards, and a canasta must contain at least four natural cards. There is no limit on the number of natural cards that can be added to a complete canasta. A wild card added to a pure canasta of course makes it mixed. Once a canasta contains three wild cards, no further wild cards can be added.
Note that in this version of Canasta, melds consisting entirely of wild cards are not allowed.

American/Modern Canasta does allow a meld or Canasta of all Wilds; but that is a less common variant than Classic Canasta. In American Canasta, a wild Canasta that contains jokers and 2s, without containing all 4 jokers, is worth 2000 points (in addition to the value of the 2s and jokers in the meld).
Source:

a complete twos canasta scores 3000 points (this is a wild canasta made entirely of twos)
a complete joker canasta scores 2500 points (this must contain all four jokers, together with three twos)
any other complete wild canasta (containing one, two or three jokers) scores 2000 points

Oh noooooooo!  I was soo pleased with myself but thank you for putting us right.

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Companion commander question
Haven't seen this covered, but can you use a companion card such as Jegantha, the Wellspring as your commander instead of as a companion?
The text on the card reads If this card is your chosen companion you may cast it once from outside the game.
Does this mean if I don't choose it as a companion I can use it like any other regular legendary creature?
Thanks.

Yes, you can.
The Companion keyword only functions outside of the game. This means that if a card with Companion is in your deck, whether as a Commander or just any regular card, then the Companion part of the card doesn't do anything; it's just a normal creature. In the case of a Commander deck, it would just be a normal Legendary Creature which is therefore valid as your Commander.

702.138. Companion

702.138a Companion is a keyword ability that functions outside the game. It’s written as “Companion—[Condition].” Before the game begins, you may reveal one card you own from outside the game with a companion ability whose condition is fulfilled by your starting deck. (See rule 103.1b.) If you do, once during that game, you may play that card from outside the game.

Commander

903.3. Each deck has a legendary creature card designated as its commander. This designation is not a characteristic of the object represented by the card; rather, it is an attribute of the card itself. The card retains this designation even when it changes zones.

Jegantha, the Wellspring is a legendary creature, therefore it can be your Commander.

Wonderful. I wasn't sure if companion was a requirement or a choice. Thank you!

@ragazinski If this answer was helpful and a better one doesn’t come along, please mark it as “accepted”, thanks!

In this case then, the deck wouldn't have to meet the companion condition?

@BadPirate Correct.. the entire companion ability would just be ignored as if it weren’t there.


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Does Masquerade affect all players?
Does a player who played the Masquerade card also have to pass a card or is it just all the OTHER players that have to pass a card?
Does the passed card go immediately into their hand or discard pile for all players?

Yes. To their hand. And it's interesting that Masquerade isn't an attack card

The Masquerade card wording is (emphasis mine) -

Each player with any cards in hand passes one to the next such player
  to their left, at once. Then you may trash a card from your hand.

The card says 'Each' which will mean every player including the one who played it.  It does not say 'Other'
Compare this with the wording on the Witch card

Each other player gains a Curse.

In that situation it is very specifically the other players.  If Masquerade meant to refer to just other players it would use the word other.
The card is 'passed' to a player's hand.  Note if it used the word 'Gain', it would mean it goes into your discard pile instead.


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Taranika, Akroan Veteran's ability
When Taranika, Akroan Veteran's ability triggers and I untap another creature, can I declare this creature as an attacker as well? Or maybe attackers are already declared? What happens here?

No, it is too late to declare another attacker; the triggered ability won't even trigger until it's too late, and after it triggers it must go on the stack and resolve.
From the rules:

Declare Attackers Step

508.1. First, the active player declares attackers. This turn-based action doesn’t use the stack. To declare attackers, the active player follows the steps below, in order. If at any point during the declaration of attackers, the active player is unable to comply with any of the steps listed below, the declaration is illegal; the game returns to the moment before the declaration (see rule 725, “Handling Illegal Actions”).

508.1a The active player chooses which creatures that they control, if any, will attack. The chosen creatures must be untapped, and each one must either have haste or have been controlled by the active player continuously since the turn began.
[...]
508.1m Any abilities that trigger on attackers being declared trigger.

508.2. Second, the active player gets priority. (See rule 117, “Timing and Priority.”)

508.2a Abilities that trigger on a creature attacking trigger only at the point the creature is declared as an attacker. They will not trigger if a creature attacks and then that creature’s characteristics change to match the ability’s trigger condition.
508.2b Any abilities that triggered on attackers being declared or that triggered during the process described in rules 508.1 are put onto the stack before the active player gets priority; the order in which they triggered doesn’t matter. (See rule 603, “Handling Triggered Abilities.”)

This does mean that you can target another creature that attacked along with Taranika, to untap that creature and also buff it.

If they could have granted the creature vigilance they probably would have, but by the time the trigger resolves any other attacking creatures are already tapped, so they used this as a workaround instead.


text:
Why does this player not have a straight?
I'm relatively new to poker so bare with me.
Community cards: J, Q, K, 2, 4
P1: A,6
P2: Q,Q
A site determined that P2 won with three of the kind. Is this wrong? How does player P1 not win with a straight by playing only 1 hole card? The way this was graded confuses me!

P1 does not have a straight.  P1s best hand is A,K,Q,J,6

can you explain when you are allowed to play one hole card?

Upon a second reading; I do not think this is a duplicate. The linked question and answer never defines what a "straight" is; and the quesiton/confusion here seems to be over what counts as a valid straight.

@StartPlayer As the one who wrote the answer to that, I updated the descriptions to clarify that such a hand is NOT a straight.

Personally I think it would be better to not try to fit this question under the umbrella of the other question. Even though the asker didn't realize it; the question was one of poker terminology (not knowing what qualified as a "straight") while the linked question is one of how to properly compare 2 hands to determine which is better. Just because the answer to the other question can be made more comprehensive to include the definition of a straight doesn't mean that this is a duplicate question.

I edited the subject to match the primary focus of the body, and removed the one sentence near the end of the body that is actually asking a different question (one that would be a duplicate of the linked question).

With the edits I agree that this question should be reopened as it is now clear about what is being asked and not a duplicate of what is a winning hand.

I felt the question was asking why hand B beat hand A.  the question was not (why do they not have a straight) but why did they not win WITH a straight.  What I felt was a duplicate question covers what is a straight.

@moam8732 What you think of is called round-the-corner straight. This does exist as a variant in house rules, but is not a part of the official poker rules. https://en.wikipedia.org/wiki/Non-standard_poker_hand

The problem is that a straight cannot be made with an Ace in the middle of the straight. Ace can be considered either the lowest card (forming a straight with A, 2, 3, 4, 5); or the highest card (forming a straight with 10, J, Q, K, A). It cannot be both low and high at the same time; so J, Q, K, A, 2 is not a straight.
In the case of this hand, player 1's best hand is A,K,Q,J,6; which doesn't form any combination; it is simply an Ace-high hand.
https://wiki.c2.com/?PokerGame

The ace is the highest-ranking card in the deck, followed by the king, the queen, the jack, and the numbered cards in order. The 2 is the lowest-ranking card. In some hands, however (such as the straight and straight flush), an ace can be used as a "1" card - Ace, 2, 3, 4, 5 is a valid straight, as is 10-Jack-Queen-King-Ace. The ace cannot be in the middle; one cannot form a straight with Queen-King-Ace-2-3.

Another source, since there is no one difinitive rulebook for Poker to cite:

The best possible straight in poker is the Ace-high straight (TJQKA) often referred to as “broadway”. The Ace can also be used to formulate the lowest possible straight A2345, often referred to as “the wheel”. Note however that it is not possible for the Ace to appear in the middle of a made straight. I.e. QKA23 is actually just Ace-high, not a straight.

Note that you never get to choose "how many" hole cards you play. You always play a total of 5 cards; whichever 5 of the 7 options give you the best hand. IF player 1 had been holding a 10 instead of a 2, then player 1 would automatically play 10, J, Q, K, A; and would win the hand because of the straight, playing 1 hole card as you suggest.


text:
How to remove Broken Fall Enchantment from play
I was playing Commander with a couple of buddies the other day. One of them had a 10/10 creature and Broken Fall enchantment in play to regenerate said creature. One of the other players cast a destroy target enchantment instant on Broken Fall. The player with Broken Falls responded by putting it back into his hand, activating the text for regeneration and putting that regeneration onto the 10/10 creature.
   If that was played correctly by the Broken Fall player, how then do you ever get rid of the Broken Fall enchantment when he can just protect it by putting it back into his hand, still protecting his creature and then just replaying it again on his turn?

You have two separate goals here:  Removing the enchantment, and removing the creature.
Removing the creature is the easier of the two problems
Regeneration only protects against lethal damage and 'destroy' effects.  That means that a creature with a regeneration shield can be removed by -X/-X effects, exile effects, forced sacrifice effects, Pacifism effects, and many, many more.
Furthermore, there are some older spells, such as Terror and Wrath of God, which ignore regeneration entirely.
Finally, regeneration only works once, so a second kill effect will work if you can play it before Broken Fall is played again.
Removing Broken Fall permanently is harder
When an activated ability is activated, all costs are paid and then the ability is placed on the stack.  This gives opponents a chance to respond to the ability - but the cost cannot be responded to.  This makes permanents that bounce themselves as part of a cost very difficult to deal with, as you can't target them in reaction to their activation.  (Even if you could, they could just activate it a second time, and still escape)
The only way to target Broken Fall without it escaping back into their hand is to do so when they can't activate its ability, which is a very narrow set of circumstances:
1) There are no legal targets on the battlefield - that is there are no creatures at all, or all the creatures present have hexproof (and are controlled by opponents) or shroud.
2) The activated ability has been blocked (for example by Pithing Needle)
3) Split Second is in effect and nothing can be placed on the stack.  Of course, Split Second also keeps you from playing anything, so unless the split second card you played was Krosan Grip, its not going to be very helpful.
However, once Broken Fall has returned to the player's hand, it is a lot more vulnerable.  There it can be discarded, or countered when they try and play it again.
There is at least one more way to deal with Broken Fall on the battlefield - create a board state where your opponent would rather let it die than save it.  This is of course very situational and tricky to do (especially as it depends on your opponent), but can be accomplished by cards such as Doom Foretold.  If your opponent has to chose between sacrificing their 10/10 or sacrificing Broken Fall, then they might decide that it is better to lose Broken Fall than to lose their creature.  Of course, the downside of this strategy is it only works if Broken Fall is the least valuable part of their board!

And there is, of course, the ultimate work around: Mindslaver them, and then do whatever you want while they are enslaved!

Good job not only thoroughly addressing the issue of removing the enchantment (through split second, discard, or counter) but also separating out and addressing the issue of removing the creature.

For the creature removal part, before finally, would it be good to mention for completeness instant damage between the enchantment is returned to hand and the regeneration resolved?

@MichalPolitowski. I thought about it, but you get there same result from letting your first destruction attempt resolve and then destroying it again,  so I didn't bother. If the card granted hexproof or indestructible that would be a useful strategy, though.

It's tricky to be sure. One way to get around the ability is to cast a destruction spell with Split Second. While a spell with Split Second is on the stack, players cannot cast spells or activate abilities (except mana abilities).
Krosan Grip can destroy Broken Fall. If you're swimming in mana, you could use Take Possession to take control of it.
Another option is to discard it from their hand. Brain Pry, Cabal Therapy, and Dark Inquiry for example.
You can also use a card like Pithing Needle to shut down Broken Fall's ability.

It's going to be tough. As long as there is a targetable creature on the battlefield, your opponent will be able to activate Broken Fall, sending it back to his hand. And since the enchantment returning to the hand is part of the cost and not the effect, you can't even respond in between Broken Fall being activated and the card returning to the opponent's hand. Basically, almost anytime something is "about to" happen to Broken Fall, it can be sent back to the hand.
So, getting rid of it from the battlefield will be very tricky. One of the only ways to do it will be to use a spell with Split Second, which prevents an opponent from responding before the spell resolves (see Krosan Grip). Other cards which limit activated abilities will also be very useful (see Pithing Needle). Although getting rid of Broken Fall from play is tough, you can also get rid of it when it's not on the battlefield. You might have better luck getting rid of Broken Fall from the opponent's hand, by forcing them to discard it. Alternatively, you could counter the spell next time they play it, preventing it from ever reaching the battlefield.
One thing you could do to kill the 10/10 creature is to have two creature-killing spells. When you put the first one on the stack, your opponent can respond by activating Broken Fall, which will grant regeneration when it resolves. You now have the option to play your second creature killer either before Broken Fall resolves, killing the creature before it gets regeneration, or playing it after Broken Fall resolves, killing the creature after it's been regenerated from the first attempt to kill it. Broken Fall can effectively only save the creature once on your turn (unless it's somehow put onto the battlefield again), so you just need to kill it twice.

You don't even need instant destruction. It's enough that there are two. Just play the second one after the first one has been thwarted by the regeneration, and the creature will die. Regeneration only replaces a single destruction, after all.

@Arthur Oh yeah, good point. Updated.


text:
How can white checkmate black in this chess puzzle?
I was thinking about making some good chess puzzles and I found an interesting approach .
White to move.

Assuming both players try to checkmate their opponent's kings , who will win the game?

Chess is also a boardgame and we welcome these questions here.

@DenisS Just because a question is on-topic for another stack doesn't mean that it isn't also valid here. Questions about chess are allowed here too.

My bad, retracted flag

If you want to make chess puzzles, a good place to start would be using images of actual chess boards and pieces... that image you had was very difficult to read as a chess board; especially since the squares were not all the same size. You can use this website to easily create your own game states to play around with and show: https://lichess.org/editor/RR4bk/1B1ppnp1/5PnP/2pN2P1/1b6/2P2pp1/1P1P1p2/7K_w_-_-_0_1

That was a very generous edit, @GendoIkari!

Assuming white is moving up the board in the position as shown,
1.Rxg8+ Kh7
2.Rxg7#
BTW, the usual notation for Knight is N, not H.
You can also use online tools to make better pictures (and to produce more easily-shareable notation for the board).
For example https://www.365chess.com/analysis_board.php
For instance, your puzzle in FEN is
RR4bk/1B1ppnp1/5PnP/2pN2P1/1b6/2P2pp1/1P1P1p2/7K w - - 0 1

ok thanks for the information , and nice that you got the checkmate position

No need to assume. a1 is in the bottom left - white starts at a.

@HaroldEd  See the original unedited post for the ambiguity.


text:
Interactions with Razaketh and Black Sun's Zenith
I was wondering about the interactions between Razaketh, the Foulblooded and Black Sun's Zenith. If I cast Black Sun's Zenith, choosing at least 8 for X, can I use Razaketh's ability to tutor for Black Sun before he dies?

No.
The State-Based Action that would put Razaketh into the graveyard happens the next time a player would get priority after Razaketh gets the -1/-1 counters, so it happens before you get priority to activate Razaketh's activated ability.
The last chance you have to activate Razaketh's activated ability occurs before Black Sun's Zenith starts resolving, and Black Sun's Zenith isn't in your library at that point.

If Black Sun's Zenith was an instant (or gained flash), then you could make it work. You'd start by activating Razaketh's activated ability, then cast Black Sun's Zenith in response. Black Sun's Zenith would resolve first, then Razaketh would die, then Razaketh's activated ability would resolve.

No, you cannot look for Black Sun's Zenith when playing it and activating Razaketh the Foulblooded's ability.
To see why, let's look at the stack:

You play Black Sun's Zenith: this means paying its cost and placing the card itself on the stack. As per the rules:

601.2. To cast a spell is to take it from where it is (usually the hand), put it on the stack, and pay its costs, [...]

Before the X -1/-1 counters are distributed, you activate Razaketh's ability. You can't do it after, because Razaketh will be gone by then if we assume Zenith's X is 8, as you propose:

State-Based Actions [...]

704.5f If a creature has toughness 0 or less, it’s put into its owner’s graveyard. Regeneration can’t replace this event.

Razaketh's ability resolves first, but since Black Sun's Zenith is still on the stack physically, you can't look for it in your library.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/3.0/


text:
What does "gain" mean?
What exactly is meant by "gain" a card. For example, if I am asked to draw a card from my deck- have I gained the card? Or does gain only apply to cards from the lineup I gain for no cost (Cheetah,  Dark Knight )

To gain a card is to take it from the lineup and move it to your discard pile. From page 9 of the rulebook:

Gaining Cards

When a card tells a player to gain a particular card
    or a card of your choice, that card is taken and
    immediately placed in that player’s discard pile at no
    additional cost, unless otherwise directed by the card.

Additionally, if you get a card from another player that is considered gaining a card as well.

Welcome to the site! your answer would be greatly improved if you added a bit more information so that it could stand on it's own.


text:
Monopoly millionaire mortgaging of a property to pay for another property
Since an agreement could not be made.
And we take monopoly a bit to seriously in this house.
I need a perspective to end this debate.
I landed on boardwalk.  I had 167k in cash to pay for it, but I was 3k shy of having enough cash to complete the (170k) purchase.
Is it legal to mortgage another one of my properties, when the rules state "you must be bankrupt to mortgage properties", to have enough money to pay for the new property?
This is very serious and I need an outside opinion.

I just read through the relevant rules a couple times; and I think it's ambiguous/not clear.

I would say no, you are just out of luck.
Defining Bankruptcy
Since the rules I found here don't explicitly define bankruptcy, but merely list the changes from standard Monopoly rules, I will refer to the standard rules. It states

BANKRUPTCY ... You are declared bankrupt if you owe more than you can
  pay either to another player or to the Bank.

Since the rules for Millionaire state about mortgage (and other things)

IMPORTANT: You can ONLY do these things if you’re bankrupt, not under
  any other circumstances!

Since buying property is optional (the standard rules say that you may buy property when you land on it, it is not required), you don't qualify as being bankrupt.  Since you are not bankrupt, mortgaging is not an option.

You must be bankrupt before mortgaging. Since you had 167k and purchasing is optional you can’t mortgage to buy. You could have sold one or your other properties however

This adds nothing to the existing and referenced answer from over three years ago.


text:
Fate Reforged Booster Pack contains a Khans of Tarkir Fetch Land
I'm kind of new to Magic.  Today I opened a Fate Reforge booster pack that instead of containing a basic landed contained a Windswept Heath.  That is a fetch land from Khans.  Is it normal for the Fate Reforge boosters to contain Khans cards?

Yes, Fate Reforged packs may contain KTK Fetchlands.
More information at: http://magic.wizards.com/en/articles/archive/feature/fetching-look-fate-reforged-2014-12-24

Also worth mentioning here that all Fate Reforged packs contain one of the two dual land types from Khans. It's just that usually the land card is the lifegain dual that comes into play tapped, not the fetchland.


text:
Does cloning a card include color?
If Clone (for instance) comes in as a copy of a black creature and attacks and is blocked by a creature that has protection from black, how does it resolve?
What if the blocking creature has protection from blue?

Thank you very much. We ran into this instance a few times and this clears it up. Thank you!

It's as if the physical Clone card was replaced with a copy of the card being copied.
The Clone is black, so a blocker with protection from black will receive no damage. The blocker will still deal damage as normal.
The Clone is not blue, so a blocker with protection from blue will both receive and deal damage as normal.
(Its name isn't "Clone" anymore.)

An object's color is determined by its mana cost and its color indicator.

202.2. An object is the color or colors of the mana symbols in its mana cost, regardless of the color of its frame.
202.2e An object may have a color indicator printed to the left of the type line. That object is each color denoted by that color indicator. (See rule 204.)

Becoming a copy of an object adopts the copied object's mana cost and its color indicator, replacing what the copier had.

When copying an object, the copy acquires the copiable values of the original object’s characteristics and, for an object on the stack, choices made when casting or activating it (mode, targets, the value of X, whether it was kicked, how it will affect multiple targets, and so on). The “copiable values” are the values derived from the text printed on the object (that text being name, mana cost, color indicator, card type, subtype, supertype, rules text, power, toughness, and/or loyalty), as modified by other copy effects, by “as . . . enters the battlefield” and “as . . . is turned face up” abilities that set characteristics, and by abilities that caused the object to be face down. Other effects (including type-changing and text-changing effects), status, and counters are not copied.

Note: Only "printed" values are copied. The effects of Effects changing the copied object color are not copied. For example, if the object being copied is a normally-green creature enchanted by an enchantment with "Enchanted creature is black", the copy will be green.

Protection gives protection from being Damaged, Enchanted/Equipped/Fortified, Blocked and Targeted[CR 702.16].
A blocker with protection from black can't be damaged by a black attacker.

702.16e Any damage that would be dealt by sources that have the stated quality to a permanent or player with protection is prevented.

", and/or loyalty" does this mean, when I copy an enemy creature, it is his copy, if the spell doesn't state otherwise?

@Zaibis, No. Who gets to use the Planeswalker is its controller. Loyalty is the number on Planeswalkers.

Unless the card that facilitates the copying (Clone in this case) states otherwise, you copy the target card exactly. This includes it's attributes such as color and casting cost. Since you are copying a black creature and blocked by a creature with protection from black, your creature will deal no damage to the opposing creature.

I assume that by "pro-black" you mean having protection from black? If so, since clone is a copy of a black creature, it has all its copiable values, including color. Your copy will thus deal no damage to blocking creature. If that creature had protection from blue, your creature would do normal damage since it is black, not blue.

Clone copies the color of the creature.
Cards that don't copy the color will state that directly on the card.  A good example of this is the out-of-print card Vesuvan Doppleganger, which states right on the card that it does not copy the color of the creature it was copying.
Incidentally, the creature type is copied, which means if you Clone a Legendary Creature you already own, one of them has to go to the graveyard.


text:
Do cards that prevent cards in graveyards from being targeted by spells and abilities stop cards such as Crucible of Worlds?
If my opponent has Ground Seal in play and I have a Crucible of Worlds, can I still play lands from my graveyard? I know Crucible of Worlds says nothing about targeting, so I assume it would not stop me from playing lands from my graveyard.
Some other cards that I assume would fall under the same roof as Crucible of Worlds are Karador, Ghost Chieftain and Gisa and Geralf.

MTG's logic is boolean. It either uses the word target and it targets or it doesn't.

Your intuition is exactly correct - Crucible of Worlds doesn't target the land cards, so Ground Seal doesn't prevent it from working.
This is reinforced in the Gatherer rulings for Ground Seal:

Only spells and abilities that target cards in graveyards will be affected. Abilities that don’t target cards in graveyards (like the one Tormod’s Crypt has) can still affect those cards.

Alright. I assumed it was that way, but I wanted to make sure, as the combos and synergies Crucible of Worlds can give are rather powerful.

I am not sure that is a comparable card to use. Tormod's Crypt doesn't target cards because it targets the entire graveyard. "Sacrifice Tormod's Crypt: Exile all cards from target player's graveyard."

I am going to update the question with some other cards with similar effects.

@JoeW Actually, it targets a player, not a graveyard.

@Arthur Good point, not sure how I missed that when looking at it. But still doesn't target cards in the graveyard.

@JoeW That's the whole point though... it doesn't target a card in the graveyard, exactly like Crucible of Worlds.


text:
Can I respond to a draw from Gitaxan probe?
If I resolve a Gitaxian Probe, can I crack a Lion Eye Diamond before I draw?

I do not agree that this is a duplicate. Without more clarification, it doesn't sound to me like he is asking literally about responding while a spell is resolving; but rather that he poorly chose that wording without knowing the proper terminology. If it just said "cast" instead of "resolve", then it would have nothing to do with that other question, and would be answered by the answers here.

If you want to activate Lions Eye Diamond before drawing a card, you must do so before Gitaxian Probe resolves.
You can respond to another event, like your opponent playing a spell or activating an ability.
So no, there is no opportunity to respond to your spell once it has begun resolving. You will get priority after the spell resolves, and at that time you can activate your Lion's Eye Diamond.
See this question for more details:  Can a player respond while a spell is resolving?

To achieve what you're wanting, you'll have to do as follows:
1) Cast Gitaxian Probe
2) Before passing priority to your opponent, activate Lion's Eye Diamond
3) Once you discard your hand and get your mana, Gitaxian Probe will remain on the stack (and can resolve as normal).

The important thing is to remember to immediately activate Lion's Eye as soon as you cast Gitaxian Probe (BEFORE passing priority to your opponent, otherwise it will be too late (unless he responds to gitaxian probe).

Not as you have written, while Gitaxian Probe is resolving no one can do anything since no one has priority.
However you could cast Gitaxian Probe, hold priority, and then activate Lion's Eye Diamond, thus you will get to draw after discarding your hand because Gitaxian Probe has not resolved yet (as you did not pass priority). This won't allow you to look at your opponent's hand before deciding of course.

To be fair, Lion's Eye Diamond activation is a mana ability, thus not using the stack, so your second to last comment is a bit misleading.

Actually, discarding is part of the cost of activating LED, so the whole stack/mana ability discussion is a non-sequitur.

@Guvante The point is "get to draw after discarding your hand because spells and abilities resolve in the reverse order they are cast or activated" is implying that Lion's Eye Diamond uses the stack at all, which it doesn't.


text:
Does Seeds of Strength trigger Heroic three times?
Seeds of Strength has the following text:

Target creature gets +1/+1 until end of turn.

Target creature gets +1/+1 until end of turn.

Target creature gets +1/+1 until end of turn.

Sage of hours reads

Heroic — Whenever you cast a spell that targets Sage of Hours, put a +1/+1 counter on it.

So would Seeds of Strength trigger the heroic once or three?

Only once. The actual trigger condition is "whenever you cast a spell...". And there was only 1 instance of "cast a spell" happening.
IF the ability said "whenever a spell targets Sage of Hours..." then it would happen 3 times.
See the Gatherer ruling on Sage of Hours:

Heroic abilities will trigger only once per spell, even if that spell targets the creature with the heroic ability multiple times.

I would like to note that alternate trigger you mentioned "whenever a spell targets..." will probably never exist. "Targeting" isn't an action in its own right. Choosing targets is just part of the spell casting process.

@murgatroid99 There are plenty of cards that care about getting targeted, and their ability would trigger as often as they get targeted. http://gatherer.wizards.com/Pages/Search/Default.aspx?action=advanced&text=+[%22becomes%20the%20target%20of%20a%20spell%20or%20ability%22]

@Hackworth Are you sure about that? I would have actually guessed it worked the other way, and I can't find any rulings or Comprehensive Rules that say either way.

Seeds of Strength is a spell with 3 abilities, you target each one individually, and each would trigger e.g. Sage of Hours.

I'm not sure about that interpretation. If the spell's abilities counted as abilities for the purpose of the triggered ability, the use of the phrase "spell or ability" would be oddly redundant. In any case, I don't think these comments are the proper place to figure this out, so I asked a question about it here

Actually, I believe I have to revert my comment. 603.2d is the reason. In part it reads "Some trigger events use the word “becomes” (for example, “becomes attached” or “becomes blocked”). These trigger only at the time the named event happens—they don’t trigger if that state already exists", so an object can only "become" a target of a spell once. After the first targeting, it's already the target of the spell, and can't become so again.

That second paragraph is wrong.

@ikegami, How is it wrong? 603.2d doesn't apply here, because it's not "becomes targeted." I'm pretty sure the phrasing I used is never used on any MTG card, so perhaps it's not helpful to have in the answer, but I thought it would be good to show the contrast between the actual trigger conditions.


text:
Can Supply-Line Cranes supply themselves?
When Supply-Line Cranes enter the battlefield, put a +1/+1 counter on target creature.
Can the cranes target themselves?

Not only can you, that's the beauty of it! A 3/5 for 5 is totally playable in limited. And at worst, that's what this guy is. But if you have a character with deathtouch, doublestrike, or even just a small flier that you'd like to survive against other 1 and 2 power fliers, you can put that +1/+1 on him.

Yes. It is a valid target because it is on the battlefield when the trigger happens. What happens, in order:

Supply-Line Cranes enters the battlefield.
The game checks for any triggers that happen as a result of this event.
Supply-Line Cranes' trigger is found, and it triggers.
You put the trigger on the stack, and must choose a target at that time.
Supply-Line Cranes is a creature (and it's on the battlefield) at this time, so it is a valid target for you to choose.
When the trigger resolves, Supply-Line Cranes is still a valid target, so it resolves, putting the counter on Supply-Line Cranes.

The other answers are correct, but fail to mention that you must choose the target when the triggered ability goes on the stack, so it matters that it's a valid target when it triggers, not so much that it's a valid target when it resolves. (If it stopped being a valid target before it resolved, because it were destroyed with an instant or something, then the ability would be countered and go away. But it would still have been a valid/legal target in the first place).

In this text, Target creature can be any creature, Supply-Line Cranes is a creature, and - quite rightly said above - is on the battlefield when the ability resolves.
If the word "another" was placed before target creature in this text, this would mean any creature bar Supply-Line Cranes.

It makes no difference who is on the battlefield when the ability resolves. What matters is that Supply-Line Cranes is on the battlefield when the ability triggers.

Yes.  The "When" phrase makes that a triggered ability, that triggers once the cranes are on the battlefield.  When it triggers, it is put on the stack.  When it resolves, the cranes are on the battlefield, and thus a legitimate target for the crane.

Not quite right. When the ability is put on the stack, it must have a valid target. The crane is on the battlefield, so it is valid.


text:
Can the Madman cause you to die from sanity loss? If so, can the dog retrieve him?
Two questions, both not directly addressed in the rule book.
1) During the Haunt, if I pick up the Madman card (gain 2 might, lose 1 sanity) and my sanity is already on the lowest value, do I die? Can Omen cards kill you?
2) If I did die and dropped the Madman, can a teammate send the Dog to pick up the Madman (assuming he is within 6 spaces)? Can the Dog retrieve (companion) Omen cards?

1) Yes you would die from the sanity loss. From the rule book (page 9):

Once the haunt begins, if any of your traits (Speed, Might, Sanity, or Knowledge) moves down to the skull symbol, your explorer dies.

This does not differentiate in any way between taking direct damage and any other forms of stat loss, so gaining the Madman can kill you if your sanity is already at its lowest point.
2) No, the Dog cannot carry the Madman (or the Girl). According to the rule book (page 7):

Some omens, like the Dog, aren’t items at all, so they can’t
  be dropped or traded. They’re companions that follow
  the explorer who has custody of them. (The Dog, Girl, and
  Madman all work this way.)

and according to the Dog card:

Once during your turn, the Dog can move to any explored room up to 6 spaces away, using doors and stairs, and then return. It can pick up, carry, and/or drop 1 item before it returns.

The Dog explicitly states that it can only pick up items. The rules explicitly state that both the Madman and the Girl are not items, so therefore neither of them could be carried by the Dog.

I have played this game several times, and the way we played was as follows (regarding your questions):
1) You die from the loss of Sanity.
2) The dog can pick up the omen if he has enough mouvement to make it to the room (where the Madman is) and back.

Was this just the best you could figure out or is it based on rules you found?

In the time, when I played, I am 99% sure I read up on it. However, as I said in the first post, "the way we played". I did not go read up when I posted this. I thought I would give the information and hope someone else would complete.


text:
"Conduit of Ruin" and "Endless One"
If I have a Conduit of Ruin on the battlefield and say that I will be casting Endless One for 10 mana, will the cost reduction of 2 mana from the Conduit of Ruin's effect reduce the X so that the Endless One is 8/8 or will it remain 10/10?
My thinking is going with X = 10, but I need to make sure.
Then, expanding on that:
If I have 4 x Conduit of Ruin on the battlefield, could I cast an 8/8 Endless One for "free", using only the total cost reduction of 8 mana (from the 4 x Conduit of Ruins) as the "X" casting cost?

You might think of it like this (summarizing the answers, which is why I put it as a comment which can be temporary): Conduit changes the cost, it doesn't change the X.

Your first and second example process the cards differently. If you reduced X from the amount of mana you want to pay for each Conduit like you did in the first example it would be a -8. The Conduit allows you to increase X without spending more mana, not decrease it from the amount spent. So for 10 mana you can get a 12/12 not an 8/8.

Yes, your interpretation is correct. From the card rulings:

Conduit of Ruin’s last ability doesn’t change the mana cost or
converted mana cost of any spell. It changes only the total cost you
actually pay.
If you control more than one
Conduit of Ruin, the last ability of each of them applies only to the
first creature spell you cast each turn, not to different spells; if you control two Conduits of Ruin, the
first creature spell you cast each turn will cost {4} less.
If the first creature spell you cast in a turn has {X} in
its mana cost, you choose the value of X before calculating the
spell’s total cost. For example, if the first creature spell you cast
in a turn has a mana cost of {X}{G}, you could choose 2 as the value
of X and pay {G} to cast the spell.

So, the value that you pick for X is fixed, the only thing that changes is what you actually pay.

You choose a value for X which is then reduced by two colourless mana for each conduit you have on the battlefield.

If I have a Conduit of Ruin on the battlefield and say that I will be
  casting Endless One for 10 mana, will the cost reduction of 2 mana
  from the Conduit's effect reduce the X so that the Endless one is 8/8
  or will it remain 10/10?

You choose a value for X and then a slew of effects may either increase or decrease the cost. Here is the pertinent rules. It is a bit long but worth the read.

601.2a To propose the casting of a spell, a player first moves that card (or that copy of a card) from where it is to the stack. It
  becomes the topmost object on the stack. It has all the
  characteristics of the card (or the copy of a card) associated with
  it, and that player becomes its controller. The spell remains on the
  stack until it’s countered, it resolves, or an effect moves it
  elsewhere.
601.2b If the spell is modal, the player announces the mode choice (see rule 700.2). If the player wishes to splice any cards onto the
  spell (see rule 702.46), he or she reveals those cards in his or her
  hand. If the spell has alternative or additional costs that will be
  paid as it’s being cast such as buyback or kicker costs (see rules
  117.8 and 117.9), the player announces his or her intentions to pay any or all of those costs (see rule 601.2f). A player can’t apply two
  alternative methods of casting or two alternative costs to a single
  spell. If the spell has a variable cost that will be paid as it’s
  being cast (such as an {X} in its mana cost; see rule 107.3), the
  player announces the value of that variable. If a cost that will be
  paid as the spell is being cast includes hybrid mana symbols, the
  player announces the nonhybrid equivalent cost he or she intends to
  pay. If a cost that will be paid as the spell is being cast includes
  Phyrexian mana symbols, the player announces whether he or she intends
  to pay 2 life or the corresponding colored mana cost for each of those
  symbols. Previously made choices (such as choosing to cast a spell
  with flashback from a graveyard or choosing to cast a creature with
  morph face down) may restrict the player’s options when making these
  choices.
601.2f The player determines the total cost of the spell. Usually this is just the mana cost. Some spells have additional or alternative
  costs. Some effects may increase or reduce the cost to pay, or may
  provide other alternative costs. Costs may include paying mana,
  tapping permanents, sacrificing permanents, discarding cards, and so
  on. The total cost is the mana cost or alternative cost (as determined
  in rule 601.2b), plus all additional costs and cost increases, and
  minus all cost reductions. If multiple cost reductions apply, the
  player may apply them in any order. If the mana component of the total
  cost is reduced to nothing by cost reduction effects, it is considered
  to be {0}. It can’t be reduced to less than {0}. Once the total cost
  is determined, any effects that directly affect the total cost are
  applied. Then the resulting total cost becomes “locked in.” If effects
  would change the total cost after this time, they have no effect.

I think it would improve this answer to specifically say that the value of X is not reduced by the cost reduction mechanisms. Also, you posted 3 large paragraphs of rules quotations and bolded half a sentence (and that half doesn't really say anything alone). I would suggest emphasizing all of the parts that you think are relevant and/or skipping the parts that are irrelevant.


text:
Casting a spell after a spell resolves?
My question has to do with Ravenous trap.  Say my opponent casts Thought Scour targeting themselves.  Once the spell resolves they have two cards + thought scour itself in the graveyard this turn.  I want to prevent them from casting a Tasigur, the Golden Fang/Gurmag Angler.  Could I cast Ravenous trap right after thought scour resolves before they get a chance to delve their graveyard?

possible duplicate of Destroying a Planewalker before its ability is used

In order to cast your Trap you must find a way to gain priority between the resolution of Thought Scour and the casting of Tasigur, as APNAP rules state your opponent gets priority (regardless of if the stack is empty or not).

116.3b The active player receives priority after a spell or ability (other than a mana ability) resolves.

However, Tasigur can only be cast at sorcery speed. So if you could get an ability to trigger off of Thought Scour, then your opponent would receive priority with an ability on the stack. When he passes priority to you, you can cast your instant speed Trap**. The easiest way I can think of to cause a trigger would be off of the cantrip. Something like Mind's Eye should do the trick, although I'm sure there are plenty of others.
If you're unable to trigger an ability on the stack off of Thought Scour, then your opponent will be able to delve his graveyard to cast Tasigur.
** - Yes, I passed up the opportunity to say "activate your trap card". Shame on me.

Thanks!  That makes much more sense now.  Agreed, bad joke lol

No, you would not be able to prevent the cast. Because it's your opponent's turn, any time a spell resolves, they are given the first opportunity to cast spells (this is called "having priority"). So as soon as Thought Scour resolves, the game "asks" if your opponent has anything to play. In your example, they play Tasigur/Gurmag Angler, and should they choose to delve to pay for the cost, those cards are exiled immediately.
You could still cast Ravenous Trap in response to the Delve card's casting (and the cost would still be reduced), but it would only affect the remaining cards in your opponent's graveyard, and would neither affect the delve nor your opponent's ability to cast the card.


text:
Do abilities like "becomes the target of a spell or ability, sacrifice it" happen even if the spell is countered?
Do I need to sacrifice a creature with the ability "becomes the target of a spell or ability, sacrifice it" (e.g., Frost Walker or Illusionary Servant) if the spell or ability has been countered?

Can you either refer to the actual card or at least write the full text of the ability?

Yes, you will still have to sacrifice the creature even if the spell that triggered it gets countered.
Examples
Let's use Frost Walker as an example. The following events happen:

Your opponent casts Lightning Bolt, targeting Frost Walker.
Frost Walker's ability triggers.
You cast Counterspell, targeting Lightning Bolt.
Counterspell resolves. Lightning Bolt is countered.
Frost Walker's ability resolves. You sacrifice Frost Walker.

Countering Lightning Bolt does not also counter Frost Walker's triggered ability. You could, however, use Stifle to counter the ability itself.
Spellskite cannot save Frost Walker. Frost Walker triggers immediately upon being targeted. Frost Walker's ability does not care if you redirect the target to Spellskite.
Standard Bearer can save Frost Walker, at least from spells that only have one target. If your opponent targets Frost Walker, you say "That's illegal. You have to target Standard Bearer." The game then rewinds to the point before your opponent cast the spell.

Let us continue this discussion in chat.

You still sacrifice the creature, even if the original spell is countered.
If a creature has the ability:

When [this creature] becomes the target of a spell or ability, sacrifice it.

and a spell or ability targets it, the following happens in your scenario:

The spell or ability goes on the stack, targeting the creature.
The creature's ability triggers, and goes on the stack.
The counter spell goes on the stack, targeting the original spell or ability.
The counter spell resolves, and the original spell or ability leaves the stack.
The creature's ability resolves, and you sacrifice it.

Once the triggered ability is on the stack, removing the spell or ability that originally triggered it doesn't do anything to the triggered ability.


text:
Can Turn to Frog prevent 'enter the battlefield' abilities?
Can my opponent cast Turn to Frog, to prevent 'Enter the battlefield' abilities?

Typically, if you have several questions that are not dependent on each other, you should ask them in separate threads.

Possible duplicate of When Turn to Frog changes a creature's base power/toughness to 1/1 do any affects that change creature's power and toughness still apply?

The first part is a duplicate of this question as Drunk Cynic pointed out, but probably not the second part. So to keep this from being closed as a duplicate, I'm going to edit to leave just the second non-duplicate question, which seems well worth having!

No, Turn to Frog can only be cast on creatures that have already entered the battlefield, so it can't prevent ETB abilities from triggering.

Turn to Frog is setting P/T, that's layer 7b. 7a is for things like Tarmagoyf (or Veteran Warleader for an example in current standard).

The answer to the other question is a little more subtle: if the creature entering has an ETB trigger, Turn to Frog can't stop it, but if a creature has a "whenever a(nother) creature enters the battlefield" ability, Turn to Frog can stop it if cast in response to casting another creature.

I went ahead and edited this down to just the non-duplicate question - sorry for making some of your answer not apply, but as you said, multiple questions should be separate, and one of them was already there. You could post another answer on the dup if you want!

The current situation here isn't good... the accepted answer has little to do with the current question.

I REALLY wonder why I get 2 downvotes on my answer. That is usually reserved for blatantly wrong answers, which mine obviously isn't, and since the OP accepted mine, it is clear he did not ask about fringe cases such as creatures triggering on other creatures entering the battlefield.

@Hackworth I didn't downvote, but I think people do tend to prefer reasonably comprehensive answers, even if the OP is okay with shorter ones. (It's also possible that the OP interpreted your answer as a broader statement than you actually meant it as - hard to be 100% sure what they were asking about.)

Also for what it's worth, downvotes do mean "not useful" not "blatantly wrong" - it's deliberate that people have some freedom to define usefulness. If you think that the only way something's sufficiently not useful is if it's blatantly wrong, that's fine, but not everyone has to apply that standard.

I downvoted because a significantly more comprehensive answer exists, which is a valid reason because the downvote button does not say "This answer would be useful if it were the only answer". I do not wish to start an argument about how brief answers can be good too, because I know a good brief answer when I see one.

@Hackworth No revisions of the Question provide clarification to which case of "enter the battlefield" abilities information is desired about. Further, having enter the battlefield effects in play is hardly a 'fringe' case. An associated fringe case would be an attempt to use Turn to Frog on Purphoros, God of the Forge, when the opponent had devotion, and they respond by some how loosing devotion.

There are two cases of "Enter the Battlefield" abilities.
If the ability is on the creature entering the battlefield, such as Abbot of Keral Keep, Turn to Frog isn't an answer. You can't target the creature until it has entered the battlefield. Once it has entered the battlefield, the Ability has already been triggered and is being added to the stack.
However, if the ability is on a creature already on the battlefield, such as Agent of Erebos or Ivy Lane Denizen, Turn to Frog is a valid answer. In response to any number of effects that would cause creatures to enter the battlefield, casting Turn to Frog while they are on the stack will pre-empt the ability. Turn to Frog will resolve first, affecting the target with the Enter the battlefield effect. When other creatures enter the battlefield, the ability no longer exists.

In magic, when it said "target creature", that means that the spell can only target a creature that already is on the battlefield.
Some spells can target a creature (or other permanents) that are in the graveyard, or exiled, or the players themselves, but it's said explicitly in the spell. (thanks RainBolt)
The conterspells target the spell itself and not the creature or whatever that the spell will summon
So all effects occuring when entering the battlefield already happened... and changing the force of the creature will not change that

"you can only target a creature that already are on the battlefield" - outside of the battlefield there are no creatures. There may be creature spells but not creatures.

There are spells that target permanents, other spells, cards in the graveyard, players, and cards in exile, so this answer isn't really correct.


text:
Do players have to discard when a Knight card is played?
In Settlers of Catan, when a player plays a Knight card ("Solider" card in older editions), do players with 8 cards or more in their hand have to forfeit half their hand to the bank?
This is causing a huge row in our family as I think that this forfeit rule only applies to rolling a seven and not to playing a Knight card.

No, you don't lose half your hand if a knight card is played.
The rules for 'rolling a 7 and activating the Robber' state

every player who was more than 7 Resource Cards must select half (rounded down) of his Resource Cards and return them to the bank.
The you must move the robber Proceed as follows.....

then steps 1 and 2 are stated for stealing a resource.
The rules for a solider cards state

you must immediately move the robber.  See activating the robber and and follow steps 1 and 2

It does not state everyone loses cards if they have 8 or more.
To clarify the rules for losing cards if you have more than 8 are only triggered for rolling a 7 and in no other way.

Thanks for the response. In fact I found the answer on the catan.com website FAQ's Know it all son has been informed. His response was that I could not possibly have known that at the time so I was obviously cheated. Looks like a good game (this is only my second game), but I might need to find somebody else to play it with!

Sounds like someone is a sore loser. :) Lots of kids struggle with it, especially motivated ones! Good life lessons.


text:
What would happen to other players creatures upon death?
I have Kalitas, Traitor of Ghet in play. We are playing with 3 people. If i beat one player, would the creatures he own die? So i would get 2/2 zombie tokens from his creatures?

I couldnt find theanswer in that post, probally im not reading it right. English isnt my mother language.

According to the Comprehensive Rules (http://media.wizards.com/2017/downloads/MagicCompRules_20170119.txt), this is what happens when a player loses the game:

104.5. If a player loses the game, he or she leaves the game. [...]
800.4a When a player leaves the game, all objects (see rule 109) owned by that player leave the game and any effects which give that player control of any objects or players end. [...]

The definition of the word "die" is:

A creature “dies” if it is put into a graveyard from the battlefield.

Since a losing player's creatures leave the game instead of being put into a graveyard, those creatures are not considered to have died, and Kalitas does not give you any tokens.

Must the losing player always prevent as much damage as possible or can he just take al the damage to avoid any combat? To prevent me to get any tokens at all? Because it can influence the game in multiplayer.

@Hans There's no rule saying that players have to try to avoid taking damage.

A player does not have to prevent any damage, except if cards say they have to. No matter if the damage would be lethal or not.

@Hans I think what you're realising here is that it is possible to be abusive in multiplayer MtG, for example by making decisions which favour one of your opponents over another. The "kingmaker problem" is present in a lot of board/card games unfortunately.

You can read more about that particular thing here: https://boardgames.stackexchange.com/questions/32736/in-multiplayer-can-a-player-concede-abusively/32737

Thanks guys, indeed the kingmaker problem was occured yesterday, but that player was kind to give us both something in return


text:
How does drawing then discarding work with a full hand?
If my opponent has a full hand of 7 cards and I cast wistful thinking, what happens?
Do they discard the two cards they draw and then discard four more for a total of six cards discarded?

This is a fairly common misconception. There is no limit to how many cards you can have in your hand at a time. You just discard down to your maximum size (usually, but not always seven) at the end of turn.

No, if you cast that spell on your opponent, he draws 2 for a total of 9 hand cards, then discards 4 cards, down to 5.

402.2. Each player has a maximum hand size, which is normally seven cards. A player may have any number of cards in his or her hand, but as part of his or her cleanup step, the player must discard excess cards down to the maximum hand size.

The cleanup step is the last step in each player's turn.

If this weren't the case, being the second player would really suck, since you wouldn't be able to draw up to 8 cards on your first turn!

To be explicitly clear - the cleanup step that matters for you is the last step in YOUR turn.  That's the only time that hand size is checked.  Otherwise end-step instant draw spells that push you past 7 cards would kinda hurt.


text:
Do train stations cause an opponent's route to count towards longest route?
In Ticket to Ride Europe a player may use a train station to use an opponent's route to complete a ticket. When a player does this, does the opponent's route count toward the player's longest route? The rules do not seem to explicitly address this issue.

No they don't.  The rules explicitly state it twice.
In longest route scoring it states "Stations, and the opponents’ routes they may provide access to, do not count for the purpose of computing paths and claiming the longest one."
In rules for stations it states "A Train Station allows its owner to use one, and only one, of the routes belonging to another player, into (or out of) that city to help him connect the cities on his Destination Tickets."  So stations are only used to help complete tickets and no other use.


text:
Can non-exile related return effects bring a card out of exile?
So I stumbled upon this land, Karakas.  Can this return effect reach a card in exile?  I read the rules regarding exile, and it appears to me that Karakas' effect (and similar return/play/add effects) are fully capable of accessing the Exile Zone.

Related: the first section of this article talks about why there aren't really cards that can do this: http://archive.wizards.com/Magic/magazine/Article.aspx?x=mtg/daily/mm/194

Karakas' ability:

Tap: Return target legendary creature to its owner's hand.

Karakas returns a creature. Creatures only exist on the battlefield, everywhere else they are usually creature cards (or spells, on the stack).

109.2. If a spell or ability uses a description of an object that includes a card type or subtype, but doesn't include the word "card," "spell," "source," or "scheme," it means a permanent of that card type or subtype on the battlefield.

So Karakas can not target cards in exile.

No, it can't. Only cards that explicitly state that they can return something from exile can do so. Examples are very few.

Riftsweeper returns an arbitrary face up exiled card to library.
Misthollow Griffin can be cast from exile.
Torrent Elemental can be brought back from exile.
Pull from Eternity returns an arbitrary face up exiled card to it's graveyard.
Mirror of Fate swaps your library for 7 exiled cards (any order)
Runic Repetition returns an exiled flashback card to your hand.
Venser Diffusion returns a suspended (i.e. temporarily exiled) card to it's owner's hand.

As Jefromi points out in a comment to the answer, Mark Rosewater is not too interested in seeing this as a mechanic that gets deeply developed, because it then becomes a second graveyard. Link
Note: There are on the order of 30 cards that exile cards face down.  Here's a rough search for them on gatherer:  http://gatherer.wizards.com/Pages/Search/Default.aspx?action=advanced&text=+[exile]+[face]+[down]

The only other two I've seen are Pull from Eternity and Mirror of Fate, but Mirror of Fate is almost always a bad idea.  Unless you happen to have a Laboratory Maniac handy.

Well that sounds like a legit plan. Of course Doomsday could do that easier...

Runic Repetition is probably the other thing that should be on that list. (It's restricted to cards with flashback, though.)

Venser's Diffusion can also unexile exiled cards, but only if they're currently suspended.

In Battle for Zendikar, it looks like this might become a more common mechanic. For instance, Oblivion Sower can pull your opponent's lands out of exile: http://media.wizards.com/2015/images/daily/EN_jkt2vsve7u.png

There are a lot more cards that return cards in exile, as long as they were the ones that exiled them in the first place.


text:
Exchange Keeper Card
In Zombie Fluxx, if you play an Exchange Keepers Card, can you give them a Creeper and they give you a Keeper so you can match the goal?

No, you are exchanging a keeper for a keeper, and a keeper is not a creeper.
That said, in some varieties of Fluxx (I don't have Zombie myself), certain creepers attach themselves to keeper cards you have on the table.  If that is the case, the creeper follows the keeper.  If you are trading the keeper that has an attached creeper, the other player will take the creeper as well.

In zombie, there is no attachment.

No, a creeper is not a keeper, it's a different type of card. So it can't be affected by things that affect keepers.


text:
Humble and losing ALL abilities: Does this affect creatures with equipped artifacts?
Humble causes a creature to become 0/1 and lose all abilities.  If the target creature has an artifact equipped, giving it +1/+1, before this instant is played, does the target lose any benefits applied from the artifact?

Short Answer
The creature will be a 1/2.
Long Answer
The Comprehensive Rules define a layer system. When multiple effects need to be applied, the layer system describes the order in which they happen. Humble sets the base power and toughness to 0/1 in layer 7b.

613.3b Layer 7b: Effects that set power and/or toughness to a specific number or value are applied.

Since the equipment modifies the power and toughness by giving the creature +1/+1, we know that it applies in layer 7c*.

613.3c Layer 7c: Effects that modify power and/or toughness (but don’t set power and/or toughness to a specific number or value) are applied.

We know that 7b applies before 7c because of rule 613.3.

613.3. Within layer 7, apply effects in a series of sublayers in the order described [...]

7b comes before 7c. Therefore, the example creature is first set to 0/1, then modified to 1/2.
Trivia
In the Magic 2015 Update Bulletin, the word "base" was added to cards like Humble. This was supposed to make it clear to players that it applies before other effects that might modify power and toughness. Prior to Magic 2015, cards like Humble still worked the same way, but it was less obvious. In other words, it was a nonfunctional change aimed solely at improving clarity.
*The phrase "Equipped creature gets +1/+1" is an ability of the equipment, not an ability granted to the creature. If the equipment said "Equipped creature gains 'This creature gets +1/+1'", then it would actually be applied in Layer 6 instead.

It may be useful to state that "Equipped creature gets +1/+1" is not an ability granted to the creature, since that is actually why it ends up being a 1/2. If it were an ability granted to the equipped creature it would have been removed in Layer 6.

It is an ability of the equipment granting a P/T boost to the equipped creature as a Continuous Effect. For it to grant the equipped creature an ability it would have to be worded something like "Equipped creature gains 'This creature gets +1/+1'" or something equally awkward.

@diego Thanks for helping. I made it a footnote so that it would interfere less with the flow.

The artifact still gives the equipped creature its +1/+1 bonus, because of the order in which power and toughness are calculated:
a) characteristics (the creature itself)
b) effects that set power/toughness to specific numbers (such as Humble)
c) effects that adjust power/toughness but don't set them to specific numbers (+/- effects such as equipment and enchantments)
d) counters (+1/+1 or -1/-1)
e) effects that switch power and toughness
So after Humble resolves, the creature will be a 1/2.

Welcome to Board and Card Games!


text:
Do you lose/gain any life when you drain yourself
e.g. you activate Orzhova, the Church of Deals, targeting yourself. Do life gain conditions trigger (like Ajani's Pridemate) or not?
(it's simultaneous, so you gain 0 net life, which triggers nothing, right?)

You still get the life gain/loss trigger. Even though the net result of the ability is 0, triggers can be "created" (pending priority) in the middle of abilities resolving.

603.2. Whenever a game event or game state matches a triggered ability’s trigger event, that ability automatically triggers. The ability doesn’t do anything at this point.

603.2a Because they aren’t cast or activated, triggered abilities can trigger even when it isn’t legal to cast spells and activate abilities. Effects that prevent abilities from being activated don’t affect them.

It would mean that a life loss couldn't be prevented?

@sinsedrix Preventing life loss would be a replacement effect, which can happen in the middle of an ability resolving.

In fact, the effect can be prevented but triggers (happens) anyway?

Ajani's Pridemate would trigger in this scenario. When Orzhova's ability resolves targeting yourself, you will lose life, then gain it back. The key there is that you do gain it back, meaning you did gain life - and that's all that Ajani's Pridemate cares about.

This is the correct answer. The effect says you gain life, so you do. The folks in this forum thread agree, and the author of this "Ask a Judge" thread (whom I assume is an actual judge) agrees.

In this situation I would take the card at face value. What it is telling you is that you can have any target player lose 1 life. Then it states you gain 1 life. Even if the player you chose is yourself, you lose one then gain one in that order. Any triggers that happen as a result of: first the life that was lost, then the life that was gained, will all still trigger regardless of the player that was chosen to lose 1 life.
I would add that I'm not certain of any reason why you would have yourself lose one life from this ability but I'm sure someone here will be able to think of a situation where the life loss would help you if triggers happened from it.

Couple examples: Gonti's Machinations, First Response

@JonTheMon Those are great examples

I'm designing cards for a pair of ability words ("Hope - Whenever you gain life, ..." and "Rage - Whenever you lose life for the first time each turn, ..."), and wanted to be certain that life drain effects that target players (not just opponents) can enable both. e.g. "Rage - Whenever you lose life for the first time each turn, ~ deals 2 damage to target creature".

(like how the recent Winding Constrictor enables both "+1+1 counters matter" and energy).


text:
Can an illegal target that will become a legal target before the spell resolves be targeted?
The interaction I'm wondering about is between Bounding Krasis, Harbinger of the Tides, and Collected Company.
As a part of Collected Company's resolution, two creatures may enter the battlefield at the same time.  If both these creatures have ETB triggers, the controller gets to choose what order they go on the stack.
Harbinger of the Tides has an ETB trigger that reads:

When Harbinger of the Tides enters the battlefield, you may return target tapped creature an opponent controls to its owner's hand.

Bounding Krasis has an ETB trigger that reads:

When Bounding Krasis enters the battlefield, you may tap or untap target creature.

If a Bounding Krasis and a Harbinger of the Tides entered the battlefield at the same time due to a spell such as Collected Company, would the controller be able to target an untapped creature with Harbinger's trigger and then tap it with the Krasis trigger on top of it on the stack?

"Will become"? ha! So many things could happen to change that.

You can't choose to target an illegal target. Period. When the Harbinger of Tides enters the battlefield, it can only target creatures that are tapped at that time.

To be specific, the following rules are relevant:

603.3. Once an ability has triggered, its controller puts it on the stack as an object that’s not a card the next time a player would receive priority. [...]

[...]

603.3d The remainder of the process for putting a triggered ability on the stack is identical to the process for casting a spell listed in rules 601.2c–d. If a choice is required when the triggered ability goes on the stack but no legal choices can be made for it, or if a rule or a continuous effect otherwise makes the ability illegal, the ability is simply removed from the stack.

601.2c The player announces his or her choice of an appropriate player, object, or zone for each target the spell requires. [...]


text:
Can I steal a creature then block my own attack with it?
My opponent casts a creature. During my turn, I attack and cast Temporary Insanity on the creature and want to force it to block my attacker.
My opponent claims that since I control the creature and it is my turn, I cannot force the creature to block, since when I am attacking, only the other player gets to designate blockers. That does not make a lot of sense to me, since it seems that the entire point of the card is to put the creature in a disadvantageous position (such as force it to block a creature you know will kill it), but we wanted to find out how this actually works.

Welcome to the site! If you type card names like [mtg:Card Name], then a link to the card on the Gatherer will automatically be generated. It's a handy feature.

Your opponent was correct. Only creatures controlled by the defending player may be declared as blockers. "Control" doesn't just mean "you decide what it does", it means you control it just like all your other creatures. It's on your side of the battlefield now (temporarily).
But there are still an awful lot of nasty things you can do with a card like Temporary Insanity. For example:

When your opponent attacks you, you can steal one of their creatures and use it to block another of their creatures. (Temporary Insanity is an instant!)
You can steal your opponent's creature and use it to attack them. (Even better if they have to block it and/or kill it to stay alive!)
You can steal your opponent's creature and sacrifice it, if you have a way to do so (for example if you have a Butcher of the Horde).

And plenty of other things - those are just among the most common.
The only way you can force your opponent's creatures to block your attack is with cards that explicitly affect how blocking works. For example, Lure forces your opponent's creatures to block a specific one of yours. Or Brutal Hordechief will let you entirely choose how blocks happen!


text:
Bazaar Trader combo and Void Snare - Ownership vs. Control
I use Bazaar Trader and Act of Treason to gain control of a creature my opponent controls.
If my opponent uses a card such as Void Snare on that creature, does the card go to my hand or my opponents hand?

I'm confused, why is Bazaar Trader in this?  Isn't your question about Act of Treason?  Bazaar Trader gives your opponent control of one of your creatures.

@John by using Bazaar Trader, I can permanently gain control ( but not ownership ) of the opponents creature that I temporarily borrowed with Act of Treason.  Bazaar Trader either gives my opponent a card or asserts ownership over one.

As you note in your title, there is a difference between ownership and control.

110.2. A permanent's owner is the same as the owner of the card that represents it (unless it's a token; see rule 110.5a). A permanent's controller is, by default, the player under whose control it entered the battlefield. Every permanent has a controller.
  110.5a A token is both owned and controlled by the player under whose control it entered the battlefield.

So clearly, we know the owner of the card, and where it goes as a result of void snare.
But let's say, for some reason, it said controller's hand instead of owner's hand. That's already covered: cards only ever go to their owner's hand.

400.3. If an object would go to any library, graveyard, or hand other than its owner’s, it goes to its owner’s corresponding zone.

As for who the owner is, well that's also defined for us:

108.3. The owner of a card in the game is the player who started the game with it in his or her deck. If a card is brought into the game from outside the game rather than starting in a player's deck, its owner is the player who brought it into the game. If a card starts the game in the command zone, its owner is the player who put it into the command zone to start the game. Legal ownership of a card in the game is irrelevant to the game rules except for the rules for ante.

this is disappointing for me and great news for my friend.  thank you!

@JacobRaccuia As 400.3 indicates, the game never places your property in a position where it could be confused for someone else's property. Far too easy to accidentally leave your card in someone else's deck that way (or for someone to dispute that it was yours in the first place).

That's been the idea all along, I would imagine. And these days so many people are using sleeves, that would be... a little strange.

"A permanent's owner is the same as the owner of the card that represents it." - But do the rules define who is the owner of the card? Normally this would be the person who is actually the literal owner (outside of MTG rules) of the card... but if you're playing with a friend's deck or something, then I assume you're the owner of all cards in the deck during the game. Do the rules define this?

Yes, that is defined. I edited that in just now.

More to the point, Act of Treason by itself only lasts for one turn. Void Snare is a sorcery speed card, which means it can only be played on the turn of the active player. By the time your opponent could play void snare, it'd be of no effect.
If you want to circumvent all of these effects, look into a Conjurers Closet or Momentary Blink.

Yes, Act of Treason only lasts for one turn. That's why he also uses Bazaar Trader: to permanently give himself control of the creature once he temporarily has control of it, by targeting himself. This comment doesn't actually answer the question in any way, it just suggests using a combo like the one in the question to achieve the goal described in the premise of the question.

@Travis, Please don't leave comments as answers.