text:
Ambiguous mission objectives and scenarios
In the newer form of Mission Risk (link), where each player has 4 mission cards of varying difficulty, there are a number of ambiguities that are not covered by the manual. After an exhausting (if not exhaustive) search of the intertubes for an official stance on mission objectives (particularly relationships between similar missions), I have landed here to seek advice.

Overlapping objectives
This is when different mission cards can be fulfilled (in part or in full) from actions taken to complete other missions.
This was brought to a head in my last game, where I had the following 3 missions: "Conquer 4 territories", "Conquer 1 territory on 4 continents" and "Take 1 territory from each opponent". Do these objectives need to be completed independently, or can a single conquest count towards each mission?
I was tempted to say that they were, but, in another recent game, I had "Control 2 continents" and "Control 3 continents". If treated the same as the first example, that's nearly the entire map and therefore way more difficult than almost every other mission.
Update (2012-01-30): Using the 3 Mission Cards from the first paragraph, let us say that in my opening turn I manage to conquer 4 territories on different continents, all owned by different players. This fulfils the objectives of each Mission Card. Am I entitled play all 3 Mission Cards over the next 3 turns?
Is there a distinction between the two types of mission other than their relative difficulty, and if that is the only distinction then how is the line drawn?
Sparse reinforcements
Also in a recent game, I had the mission "Gain 18 reinforcements this turn" (played after gaining reinforcements). I gamely attempted to suggest it might be possible to play this mission after eliminating another player and playing the captured territory cards for further reinforcements.
My argument went that it satisfied both criteria of being "after gaining reinforcements" and occurring within "this turn" as specified by the mission description.
Nobody else agreed and I accepted that it was a stretch, but I'm keen to hear thoughts.
Eliminated players
Somebody other than me tried to claim that a player eliminated that turn (by them) should count for the purposes of the "Have twice as many territories as any 1 enemy". This was swiftly rebuffed. Edit: We assume an implied equal-to-or-greater-than for all quantity-based missions, so the mission in question would, for practical purposes, read "Have at least twice as many...".

In short, any general rule or standard that could be consistently applied to any combination of overlapping/ambiguous mission combinations would be greatly appreciated.

I added a new short answer section that tells you where in the rules the answers to your questions. The only thing without a direct answer what is 2x zero.

Joe - Welcome to B&CG, when asking multiple questions it would be best to split them up into individual questions.  This allows the questions to be answered individually which enhances voting (How do you vote when you agree with the first answer but not the second after all?)  Also, individual questions can have distinct titles that are on point.  Your title here provides little value.  Splitting these up is the way to go.  Thanks.

Pat - Would you like me to split up this question now, or just all future questions?

Overlapping Objectives: You may only complete one mission per turn, even if you have achieved the objectives on multiple mission cards, and only on the turn which you achieved the objective. On page 17, under Completing a Mission (emphasis mine).

Completing a Mission
You may claim a completed mission once you have achieved what it says on the card. But you cannot claim more than one mission on a turn.

Update: You may only complete missions if you achieve the objectives that turn. There are 3 examples of when mission cards can be claimed.
1) Play at the Start of your Turn: before Reinforcements.
2) Play after you gain Reinforcements: show when you receive reinforcements (either during the reinforcement step, or at any time you have 5+ cards in hand)
3) Play at the end of your Turn: after drawing a territory card (if applicable).
I imagine it would be a nightmare if you would be required to remember all a players action since the beginning of the game as proof that you did/didn't complete some mission objective. The rulebook doesn't state clearly that you have to complete the mission objectives on the turn that you claim the card, but years of Risk history would indicate that this is the correct interpretation. This would further be clearer if the "Control X continents/territory cards" all had (play at the Start of your Turn) since you cannot change the number of continents/territories you control until your combat step, the "Conquer X continents/territory cards" all had (play at the End of your Turn) after your combat step, and all "Gain X+ reinforcements" cards with (play after you gain reinforcements) since that is when you gain reinforcements. The alternative, of counting all your actions since the beginning of the game, would make it easy to complete many of the missions +3 troops per turn allows you claim 18+ troops on turn 6, conquer X+ territories cards would require a pen & paper to keep track of, etc.
As for the differentiating factor for the Mission Cards, they are sorted by the type printed on their card backs (page 17), General, Major, Colonel, Captain. I would surmise that they there are differing levels of difficult in completing these goals, but the rulebook doesn't say.

Sparse Reinforcements: You may only use an opponents territory cards to gain further reinforcements during a turn, if you have 5+ territory cards in hand. The rules specifically state the steps in your turn on page 7. You will note that Combat happens after Reinforcements. You can only gain a players territory cards from eliminating them during Combat, so it is too late in your current turn to purchase reinforcements during your normal Step 1. The only exception to this is on page 12, under Eliminating Another Player: that says, "if your new hand of Territory cards is now 5 or more, you must stop immediately turn in a set in for bonus reinforcements. Since you may play the mission card after gaining reinforcements, you can play it during this bonus reinforcement step. You probably can also count any reinforcements you have gained since the start of this turn (during Step 1), and any troops you gain during this bonus step towards fulfilling this requirement.

Step 1: Receive and Place Reinforcements (always)
Step 2: Combat (if you like)
Step 3: Fortify your Position (if you like)
Step 4: Collect a Territory Card (if you have conquered at least one territory)

Eliminated Players: Yes, any number of territories is twice as many as zero.

I agree with this statement. An eliminated player clearly has zero territories, and zero times any number is zero (2 x 0 = 0). Therefore, any number of territories (including 0) would be having twice as many territories as any 1 enemy.

0 - 0 or more
1 - 2 or more
2 - 4 or more
...

A couple of issues: 1) I wasn't referring to playing multiple cards on the same turn. See my update of the "Overlapping objectives" section of my Q for more details. 2) On page 12 under "Eliminating Another Player", it says "If your new hand ... is now 5 or more, you must stop and immediately turn a set in for bonus reinforcements.", which contradicts what you stated.

@QuickJoeSmith, I updated my answer. I didn't catch the 5+ territory cards exception as the PDF was an image only, and not text searchable.

On further reflection, the conquer n territories/eliminate n units do seem to make the most sense in terms of their difficulty (General/Colonel/Major/Captain) if you have to complete them in their entirity in one turn.


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Smallworld: Can the sorcerer's ability be used on a lost tribe token?
From the rulebook: "Sorcerers can conquer a Region by substituting one of your opponent's Active tokens with one of your own taken from the storage tray".
In this case, is the lost tribe token consider an opponent?

Lost tribe tokens are neither an active race nor under the control of an opponent, so they clearly can't be the target of the sorcerors' ability.

The Sorcerer's power can not be used on the Lost Tribe tokens.
Source: http://boardgamegeek.com/thread/391216/what-we-know-so-far-clarification-of-rules

source: Stack Exchange

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sort: votes


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When can cards/power ups be played in King of Tokyo (and Power Up! expansion)?
I think these is how the cards can be used:

Keep cards can be played only during your turn.
Discard cards are to be played immediately.
Permanent power ups can be played only during your turn.
Temporary power ups can be played at any time.
All cards/power ups can be played in the turn you bought/acquired
them (unless stated otherwise).

Please correct me if I'm wrong. Thanks!

The King of Tokyo rules only define two types of cards, Keep and Discard. (Page 2). There is no such thing as Temporary or Permanent cards. Many cards seem to represent power ups of the Monsters, but this isn't a game term.

Card Description
How to play the card is indicated above the description of the effect.
KEEP: Monsters keep these cards for the remainder of the game (sometimes the card will indicate it is discarded under certain circumstances.)
DISCARD: Monsters immediately resolve these then discard them.

As the Card Description indicates, the cards themselves will indicate when they can be played, with the exception of DISCARD cards that are played immediately after being purchased. Unless a card notes otherwise, you may play it and gain its effects immediately.
Permanent/Temporary Evolution cards can be played at any time, barring a timing restriction printed on the card. From the expansion rules (page 2)

Evolutions - Monsters keep their evolutions secret until they want to play them – which can be at any time. There are two kind of Evolutions:
Temporary Evolution: They are discarded after being played.
Permanent Evolution: They stay in play like a Keep card from the base game.

The power ups are for the expansion. I will update my question.

Thanks for the update. I guess the first sentences of the answer no longer apply. It'd be nice to clean them up :)

My understanding is:
Keep Cards
Come into effect as soon as you buy them and remain in play until you die, unless otherwise stated or some other card removes it (e.g. you sell it using Metamorph, someone buys it off you with Parasitic Tentacles).
When you can use the extra abilities given to you by a card is specific to the card and is generally stated on it. Examples:

Eater of the Dead power is usable at any time, so if a player dies when it's not your turn you still gain points.
Parasitic Tentacles power can only be used during the phase of your turn where you buy cards.

Discard Cards
Discard cards are played immediately upon buying and the effects are resolved immediately. So for example if you wanted to buy 2 discard cards on your turn you would buy the first card and resolve it, then buy the second card and resolve it.
Buying Cards
Normally you can only buy cards on your turn, however Opportunist allows you to buy cards when it's not your turn. If you use Opportunist to buy a card then that card has immediate effect, you do not wait until your turn to resolve it.

Thanks for the answer. I was also wondering about the power ups in the expansion. I will update my question.

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In Star Fluxx, have you needed to change how The Computer and The Unseen Force play?
Star Fluxx has a number of cards that end up being quite powerful and can throw chaos into a game that seemed to be almost over. Most of these cards are either Actions or Surprises and can thus only be used once for each time they are drawn. However, the two Keepers, The Computer, and The Unseen Force seem to provide decisive long-term advantages.

The Computer - If you have this card on the table, Draw and Play one extra card per turn. Also, you may exceed Hand and Keeper Limits by one.

Unseen Force - *If you have this on the table, once per turn you can steal a card chosen randomly from another player's hand, and add that card to your own hand.
I come from a long history of playing control decks in Magic: The Gathering and so I try and dig deep into the strategy of how to accrue small advantages and deal with random elements in card games. Star Fluxx has significant random components to the point that sometimes a player can win in a single turn when no one suspected that they were even close to victory. To me, this suggests that the best strategies will be those that rely on drawing more cards than your opponents and playing more cards than your opponents, rather than striving for any specific combination of cards or rules.
I have a small sample size, but I have only lost 1 game where I controlled The Computer or The Unseen Force for more than 2 turns (I have won the other 5). Star Fluxx, though, is more about having fun through narrative and social interaction than min-maxing. The problem I am running into is that these cards seem to reduce the fun that the other players are having because they recognize that they're being slowly ground into a defeat.
Have you had the same experience with these 2 Keepers? Have you instituted any house rules to modify these cards?

It sounds like you've played a lot, in order to have six games where you've had both of those specific cards. Surely it's not that common an occurrence?

(I ask because playing that many times, and winning more than your friends on average, can probably contribute to feeling ground down.)

@Jefromi I only meant 6 games where I had 1 of those specific cards and after game 2 or 3 I started looking for The Computer with Time Portal and What Do you Want?

In a 2 player game the Time Portal/Time Traveler combo is much more game breaking.

I tend to think of Unseen Force as annoyance, whereas The Computer is probably the strongest card in the game.  There are various things you can do to try to dilute the power of an opponent's The Computer, raising the draw and play count rules and creating hand and keeper limits.  Plus you can always steal keepers or play Brain Transference.  That said, if someone pulls out The Computer at the start of the game then it is really hard to keep up with them.  There are other strong cards in the game like Holographic Projection and The Captain so it doesn't feel like the game is broken to me.
Is it possible that you are a much better player than your opponents are and it is this that grinds them down?

I was thinking about this earlier: The Computer always offers an advantage of 1 card and 1 play per turn. This way of thinking makes it seem like the advantage is constant regardless of the rules. But at Draw 4, Play 4, it offers only a 25% increase in the number of cards drawn/played. This makes it seem like the advantage is smaller with bigger rules counts. I'm not sure which is the correct analysis (though I lean toward the latter).

I can see this being an issue in a competitive tournament, but you are right, Star Fluxx is about creating a narrative and having fun with friends.
I don't think that Star Fluxx could even be played in a competitive setting, In most games that I've played the computer has indeed greatly increased the frequency of playing cards but the turnover rate for the computer has always been high.
When someone has the opportunity to take a card, the computer is always the first to go. In the games that I've played, this has never been less frequent than once every five turns.
The way to get a high turnover of the computer and the unseen force is to simply play with more people. I usually play Star Fluxx with 5 or 6 people, cards get played frequently and someone's always changing the rules, the same action or suprise card will re-appear over and over again. In these larger games the winner is basically random, but it honestly feels to me like the game was designed to be played this way.

Our games of Star Fluxx with more than 2 players tend to go very quick once everyone has the cards understood. It then becomes a game of seeing if anyone can get the time traveler and the time portal, just for kicks.
We do have two house rules to extend the game.
1 is we bring in zombie jamboree from zombie fluxx. Shuffling and redistributing the keepers and creepers can give the game a lot more longevity.
2 we bring in an extra creeper. We use the evil rabbit from monty python fluxx. We call this card the dick move card. It is considered evil, for the purposes of star fluxx rules and goals, but it has an extra action of making every OTHER player have to completely turn in all the cards in their hand and on the table. Even more than the zombie jamboree, this card can completely upset a game with 3 or more players, and extends the life of a game into 2 or 3 reshuffles of the discard pile.  This card restarts all players except the one who drew it.

We decided that if you use the "draw 1" the you MUST play 1 - if you do not draw an extra card the you DO NOT get to play an extra card - seems to be working but not to the opponent's aid :P
Unseen Force works fine oO

Problem is that the extra draw and play options are mandatory with the computer keeper.


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Monopoly (advanced) with speed die
So my family and I were playing when one of us landed on the "Go to Jail" space. They went, on their second roll to get out he rolled a double, now since we are playing the advanced game, does he roll the speed die since he is no longer in jail because he rolled a double with the white dice and then move with all three or does he just use the double white dice without the speed die? In the rules it does state not to use the speed die to get out of jail, but he did roll a double without the speed die.

According to the rulebook, you get out of the Jail if...

(2)
  using
  the
  "Get
  Out
  of
  Jail
  Free"
  card
  if
  you
  have
  it;
  (3)
  purchasing
  the
  "Get
  Out
  of
  Jail
  Free"
  card
  from another
  player and
  playing
  it;

Regarding the speed die:

Use
  the
  white
  dice
  ONLY
  when rolling
  to
  get
  out
  of
  jail.

Therefore, if you play the "get of of jail free" card, you immediately get out of jail and you roll to move, not to get out of the jail. Therefore, you do use your speed die, as you're already out.
Nevertheless, if you roll to get out of jail and you roll doubles, you still do not use the speed die, even if you succeed. It's just that when rolling to get out of jail, if you roll doubles you use that result as your move.

This answer misses the question as it looks like OP is talking about option (1) to get out of jail.

The applicable rule would be:
"Use the white dice ONLY when rolling to get out of jail."
The speed die is an extra die that can be used in roll.  This rule explicitly states that the speed die is NOT used for a roll where a player is trying to get out of jail.  When they go to make such a roll, they are in jail.  Once they roll they are no longer in jail, but have already completed their roll.
I am used to the speed die from playing Mega Monopoly where the speed die is used every time the dice are rolled.  The Advanced Monopoly has sometimes uses the classic two die roll and sometimes all three dice.  A roll is always a single event.

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Roll-and-Move Board Design
Some games (like Chutes and Ladders) have a single track that players move along by rolling a die to see how far they travel.  (These are often called roll-and-move games.)
Many of the spaces on a roll-and-move board are typically blank, just stepping stones on your way to the goal.  Other spaces are action spaces, where something happens when you land there.
Are there common theories for how a designer decides which spaces should be action spaces?
Here's an example of the type of board I'm talking about: my own game Space-Venture.

Richard, as it is, this question is unlikely to be useful to anyone else.  I'm going to try to edit it in such a way that it might be more generally applicable.  If you think my edit ruins the intent of the question, feel free to revert it back to your version -- I won't be offended!

I fear this is going to be opinion based because there is no manual on how to create games. If I had to give my opinion and make a guess at the way designers do it, I would start with the most common result of your random number generator and space the 'action' tiles so that the most common roll lands players there if they were to consistently get the most common result. This way you are almost certain to land on one of the 'action' tiles but it is not a 'sure thing'.

@Crystal Nice edit, much improved.

When you're looking at games like Monopoly or Chutes and Ladders, you're looking for fairness and equality.  Everyone is at the mercy of the dice, and you should take the dice you roll (and the probability of something happening) into account when you roll them.
Taking Monopoly, for instance, you have spaces that are your usual spaces (which are your property tiles).  When making a game with that in mind, and the fact that you want something to happen every now and then, you should space things out so the chance that someone will land on an action space is even enough.  A roll of a 1d6 (one six sided die) is going to be much more different then 2d6.  In fact, a 2d6 is going to be even more wildly different then a 1d12, since a 1d12 is all consistent (given the die isn't weighted) while 2d6 will produce more 7's than anything.
You have to also weigh in on if you want both negative and positive effects, only negative effects, how bad those are, ect...  This all plays into how 'randomly' your spaces are hit.  And, again, I will stress that the players have to be treated fairly in this regard.  Since they cannot choose a path or how many spaces they move, you remove the tactical and strategic thinking from that aspect of the game.  If it's something simple, like a child's game, then this makes sense.  If it's more of an advanced game, you need to bake some tactics or decision making into the event spaces.


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What happens to a destroyed creature with two totem armors on it?
If I have a creature, with two different totem armors on it, and it's destroyed somehow (not sacrificed, not killed by -x,-x effects) what happens? Are both totem armors destroyed to save it, or just one? Can I choose which one?

Per the Gatherer ruling (for Bear Umbra, not that it matters really):

If a permanent you control is enchanted with multiple Auras that have
  totem armor, and the enchanted permanent would be destroyed, one of
  those Auras is destroyed instead -- but only one of them. You choose
  which one because you control the enchanted permanent.

The comprehensive rule behind this Gatherer ruling is 616.1. If two or more replacement and/or prevention effects are attempting to modify the way an event affects an object or player, the affected object's controller (or its owner if it has no controller) or the affected player chooses one to apply, following the steps listed below. — Since only one replacement effect "If enchanted permanent would be destroyed, instead remove all damage marked on it and destroy this Aura." is applied, the other aura isn't destroyed.


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Is death from deathtouch a state based action?
If someone attacks me with a trample creature say, 6/6, I block with a 1/1 deathtouch AND have Dissipation Field in play (returns permanents that damage me to their owners' hands),
will the wyrm go back to his owner's hand or does it die from my deathtouch creature?

Death from deathtouch is a state-based action. Specifically, this one:

704.5h If a creature has toughness greater than 0, and it's been dealt damage by a source with deathtouch since the last time state-based
  actions were checked, that creature is destroyed. Regeneration can
  replace this event.

The triggered ability from Dissipation Field will still go on the stack, but its target will be dead by the time it resolves.

The trample creature will die.

702.2c A creature with toughness greater than 0 that's been dealt damage by a source with deathtouch since the last time state-based actions were checked is destroyed as a state-based action. See rule 704.

Sequence goes like this

Damage is assigned by players.
Damage is dealt simultaneously.
Dissipation Field triggers due to damage to player.
Active player is about to receive priority, due to rule 704, game checks for state-based actions. Due to 702.2c, the trample creature is destroyed.
The dissipation field ability is put on the stack, but when it resolves does nothing, as it can no longer find the trample creature.

Just a small nitpick that doesn't change the outcome: the triggered ability is not put on the stack in step 3. That happens after state-based actions are checked. And the ability would not be removed from the stack, it would resolve normally but fail to return anything to his owner's hand.

@Pablo Fair point. Will edit accordingly.

@user1873 According to 704.3., state-based actions are checked "whenever a player would receive priority" so you're correct, triggered abilities aren't actually put on the stack and the player doesn't receive priority until state-based actions are dealt with. Perhaps my wording was unclear. :)


text:
Are cards that are both Land and Creature affected by summoning sickness?
Are cards that are both Land and Creature affected by summoning sickness with regard to:

Possibility to attack
Activating special abilities with the TAP symbol?

Some relevant cards: Dryad Arbor, Life and Limb.

Yes they are affected. No they cannot use any ability that requires {T} or {Q} as part of the cost (unless the land creature also has haste).

Dryad Arbor satisfies the criteria for being a creature. (or Charmille dryade in French)

205.2b Some objects have more than one card type (for example, an artifact creature). Such objects satisfy the criteria for any effect that applies to any of their card types.

Creatures cannot activate abilities that require {T} or {Q}.

107.5. The tap symbol is {T}. The tap symbol in an activation cost means “Tap this permanent.” A permanent that’s already tapped can’t be tapped again to pay the cost. A creature’s activated ability with the tap symbol in its activation cost can’t be activated unless the creature has been under its controller’s control continuously since his or her most recent turn began. See rule 302.6.
107.6. The untap symbol is {Q}. The untap symbol in an activation cost means “Untap this permanent.” A permanent that’s already untapped can’t be untapped again to pay the cost. A creature’s activated ability with the untap symbol in its activation cost can’t be activated unless the creature has been under its controller’s control continuously since his or her most recent turn began. See rule 302.6.

Creatures cannot attack if you haven't controlled them since the start of their most recent turn.

302.6. A creature’s activated ability with the tap symbol or the untap symbol in its activation cost can’t be activated unless the creature has been under its controller’s control continuously since his or her most recent turn began. A creature can’t attack unless it has been under its controller’s control continuously since his or her most recent turn began. This rule is informally called the “summoning sickness” rule.

Unless they have Haste, a Creature cannot attack or activate abilities that require {T} or {Q} in their cost.

702.10b If a creature has haste, it can attack even if it hasn’t been controlled by its controller continuously since his or her most recent turn began. (See rule 302.6.)
702.10c If a creature has haste, its controller can activate its activated abilities whose cost includes the tap symbol or the untap symbol even if that creature hasn’t been controlled by that player continuously since his or her most recent turn began. (See rule 302.6.)

Regular lands can give mana with {T}, and the card I wonder on has a special ability to give a green mana when it'is tapped. As it is also a land, can I tap it for mana ?

@sinsedrix, Dryad Arbor is most likely the card you are talking about. Dryad Arbor has "Land Creature" in the Type Line. You can {T} if for green mana, but because it is a creature, you cannot do so unless you have controlled it since the start of your turn (or it has haste). My answer covers the general case, as well as your particular case. What is this card you are asking about, if it isn't Dryad Arbor?

To be sure (as my english is not great), in fact the creature nature of the card prevails on its land nature and I cannot tap it (even for mana) in the first turn it comes into play? I only have the french card but the translation seems to correspond to "Dryad Arbor".

@sinsedrix,I am certain that your English is better than my French. "Charmille dryade" is Dryad Arbor. Because it is a creature, all effects, abilities, and other cards that care if Dryad Arbor is a creature, (its creature nature will prevail). Because it is a land, all effects, abilities, and other cards that care if Dryad Arbor is a land, (its land nature will prevail). Dryad Arbor's creature type does not prevent it from having the Forest ability, "{T}: Ajoutez {G} à votre réserve". Neither does Dryad Arbor's land type prevent it from being subject to summoning sickness(le mal d'invocation)

Yes, they are affected. If you play a land and transform it, summoning sickness applies as if you cast a creature directly.
You can find a similar question in the MTG Salvation forum.
Edit: This is true for attacking as well as using special abilities that require you to tap the creature.

What about special abilities?

Exactly the same. I will add this to my answer.

Though regular lands can give mana as soon as they are played, and the card I wonder on has a special ability to give a green mana when it'is tapped.

Note that a creature has summoning sickness if it was not under your control at the beginning of the turn, not only if you played it this turn.

Hackworth: Does that mean that a creature I capture using "enslave" has summoning sickness?

Sinsedrix: Which card are you talking about. Discussion will be easier if we know the card in question.

302.6. A creature's activated ability with the tap symbol or the untap symbol in its activation cost can't be activated unless the creature has been under its controller's control continuously since his or her most recent turn began. A creature can't attack unless it has been under its controller's control continuously since his or her most recent turn began. This rule is informally called the "summoning sickness" rule. Thats why cards like Threaten give the creature haste.


text:
Is it valid to exploit infinite loopholes in Magic: The Gathering?
Today at work, I played my first game in almost 10 years using a deck from another player. He was playing a deck made of creatures that facilitate life points regain. At one point, using 3 different cards, he was able to exploit a loophole that would allow him to get zillions of life points.
I remember that around the time of 3rd edition loopholes were limited to the "only once" rule, because it wouldn't make sense to abuse a loophole. MTG is so large, it's impossible not to find a loophole between cards, and there are tons of them.
So the big question, does that "only once" rule for loopholes still stand?

What do you mean by "loophole"? Something that you actually believe to be a mistake in the rules that will be fixed sometime? Or just a good combo that a good player found and built a deck around? The designers are quite aware that there are powerful combos among the cards they create.

There is a difference between a good combo like a dragonstorm deck that deals 20 points of damage on the spot and a zillion life point gain loophole...

So by loophole you mean an infinite combo? Have you seen http://boardgames.stackexchange.com/questions/4733/does-going-infinite-necessarily-end-the-game ? That is, the rules explicitly discuss what to do when there's a (potentially) infinite combo. They know that it can happen.

@MathieuDumoulin I am not sure of that.  Tournament rules explicitly detail how to deal with infinite combos.  And since there are also infinite damage combos and ways to win outside of just bringing the opponent down to 0 life, gaining "a zillion" life is probably no more unfair than dragonstorm was.

@Jefromi Thanks, didn't check for the keyword "infinite" in my search so i couldn't find it... can you add the answer i'll mark it

@TimothyAWiseman Nah, that dragonstorm was super play, played 3 spells that were used to gain mana up to 9 red mana, played a dragonstorm, allowed to put 4 dragons on the game and each dragon deals 5 damage splitted the way you want. Dealth all on other player, win the game... The other was a infinite loop with a morpher and a creature that allows artifacts to be removed from game and returned from game automatically creating an infinite loop and he also had a +1 to life points creature when a creature came into play... infite life...

I know dragonstorm well, played it in the last tournament I went to (literally the last before I stopped competing).  But there are several ways to generate infinite health and also infinite damage (technically arbitrarily large, the rules allow for it, but make you choose an actual number).  That is a combo, but not a loophole.  My point was that with other ways to win, even infinite life isn't an "instant win".  It isn't any more "broken" than dragonstorm was, and probably less.

Do you mean an "infinite loop" rather than a loophole? The former might also be called an infinite combo. The latter would be an error in the rules, or a card that was worded poorly. There are plenty of "loopholes" that have been fixed, hence the huge amount of cards which have Oracle Text that is different from some (if not all) of the printed versions of the cards.

In competitive play, definitely and without a doubt.  Something that looks like a loophole is probably just a chance to create a good combo deck and you should use it ruthlessly.  Even if it was truly an error in the rules (or miscalculation about how powerful something should be) it will be corrected by errata later, but until then use it.
In casual play, you may wish to at least give the other player a heads up that you are using a combo deck (though not necessarily what combo!).  Some casual players do not like playing against combo decks.  Then again, many casual players don't like playing against tournament quality aggro decks and it is good form to at least warn them if you are using anything close to tournament quality.

Combo decks are important for the MtG meta game. The 'Rock, paper scissors' of 'Aggro, Combo, Control' will be removed if you remove combo. Your meta will be shifted and some decks might become too powerful. Maybe you can try to build a deck that's specialized in beating combo instead of banning them?

I never said anything about banning them, they are absolutely vital in tournament play.  I said many casual players (some of which don't know what a meta game is) hate playing against combo decks.  In a purely casual environment it can be courteous (not required) to inform your opponent if you are playing a combo deck or even a deck that is tournament level.

I am not aware such a rule ever existed - infinity combos have been around from the very beginning of MTG.
What you are probably referring to is this: if there is a (potential) infinite loop that does not change the game state, then this loop may only be performed once, if the involved players have a choice about it. Since your opponent clearly changed the game state (after each loop, he has more life than before), he may perform the loop as often as he wants. See the rule and an example below.
Under the current rules, all this is covered in this section:

Taking Shortcuts

721.1. When playing a game, players typically make use of mutually understood shortcuts rather than explicitly identifying each game choice (either taking an action or passing priority) a player makes.
721.1a The rules for taking shortcuts are largely informal. As long as each player in the game understands the intent of each other player, any shortcut system they use is acceptable.
721.1b Occasionally the game gets into a state in which a set of actions could be repeated indefinitely (thus creating a “loop”). In that case, the shortcut rules can be used to determine how many times those actions are repeated without having to actually perform them, and how the loop is broken.
721.1c Tournaments use a modified version of the rules governing shortcuts and loops. These rules are covered in the Magic: The Gathering Tournament Rules (found at WPN.Wizards.com/en/resources/rules-documents). Whenever the Tournament Rules contradict these rules during a tournament, the Tournament Rules take precedence.
721.2. Taking a shortcut follows the following procedure.
721.2a At any point in the game, the player with priority may suggest a shortcut by describing a sequence of game choices, for all players, that may be legally taken based on the current game state and the predictable results of the sequence of choices. This sequence may be a non-repetitive series of choices, a loop that repeats a specified number of times, multiple loops, or nested loops, and may even cross multiple turns. It can’t include conditional actions, where the outcome of a game event determines the next action a player takes. The ending point of this sequence must be a place where a player has priority, though it need not be the player proposing the shortcut.
721.2b Each other player, in turn order starting after the player who suggested the shortcut, may either accept the proposed sequence, or shorten it by naming a place where they will make a game choice that’s different than what’s been proposed. (The player doesn’t need to specify at this time what the new choice will be.) This place becomes the new ending point of the proposed sequence.
721.2c Once the last player has either accepted or shortened the shortcut proposal, the shortcut is taken. The game advances to the last proposed ending point, with all game choices contained in the shortcut proposal having been taken. If the shortcut was shortened from the original proposal, the player who now has priority must make a different game choice than what was originally proposed for that player.
721.3. Sometimes a loop can be fragmented, meaning that each player involved in the loop performs an independent action that results in the same game state being reached multiple times. If that happens, the active player (or, if the active player is not involved in the loop, the first player in turn order who is involved) must then make a different game choice so the loop does not continue.
  721.4. If a loop contains only mandatory actions, the game is a draw. (See rules 104.4b and 104.4f.)
721.5. No player can be forced to perform an action that would end a loop other than actions called for by objects involved in the loop.
  Example: A player controls Seal of Cleansing, an enchantment that reads, “Sacrifice Seal of Cleansing: Destroy target artifact or enchantment.” A mandatory loop that involves an artifact begins. The player is not forced to sacrifice Seal of Cleansing to destroy the artifact and end the loop.
721.6. If a loop contains an effect that says “[A] unless [B],” where [A] and [B] are each actions, no player can be forced to perform [B] to break the loop. If no player chooses to perform [B], the loop will continue as though [A] were mandatory.

As a general answer to your "loopholes" remark:
I would take a radical stance and say "There are no loopholes in M:TG". Players are not required to guess the intention of the game designers, they are only required to follow the rules of the game. If the rules allow something like the "white Ball Lightning", something which was clearly not the intention in the design of Waylay, then there's nothing a judge could do about it. If the game designers consider something a loop hole, then the only things they can do is to give the card an erratum, restrict its tournament legality, or change the rules. Until either happens, players have free reign, and it's purely a question of sportsmanship and/or house rules.

Thanks for writing a more thorough answer even though you weren't first! Correcting the assumption from the question, that there was a rule against these things, is a valuable contribution, as is mentioning that infinite loops are not really loopholes.

I think the Time Vault/Wall of Roots "Wall of Boom" deck was definitely a case of exploiting a loophole.  But of course Wizards stamped that one out as quickly as they could!

@thesunneversets To be fair, the state of the game rules was so haphazard at that point that it's not clear that deck was ever actually valid - only that a judge somewhere thought it was.  (And Time Vault wasn't actually a part of the deck - just part of the rules fuzziness that led to the deck).  I don't believe that would have happened with the current state of communications (although given some of the horrible rulings I've seen at FNMs, you never know); certainly it couldn't happen at a high-level event.

Well, sure, it was a controversial ruling, but Wizards did create the possibility for it by officially creating a "between turns" phase as a sticking plaster for Time Vault problems.  That this kind of thing can and did happen certainly helped them nail down and simplify the rules into something that, fingers crossed, is watertight today.

Wow, that is a lot of rules. I was in the process of updating all of the 716 rules to their new numbers (719) but I think this needs some work beyond just updating the numbers. Consider summarizing the rules, or being more choosy about which ones to include. If the entire section is necessary in full length, then perhaps the question is too broad.

First of all, I'd suggest to have a look at the Oracle: several "loopholes" are addressed and often cards text is officially amended in order to remove them.
As a result, lots of supposed "loopholes" are short-lived.
It's impossible to give you a clear cut advice if you don't write the sequence of cards that created the "loophole" in this case.


text:
Would the +1/+1 counter from Curse of Stalked Prey save my creature?
My question pertains to a situation that happened last night when my friends and I were playing Magic: the Gathering.
There was a game of Two-Headed Giant going on and I had Werewolves on the battlefield with Trample. My partner had previously enchanted an opposing team member with Curse of Stalked Prey. I had a Reckless Waif with a 3/2 power and toughness (via Mayor of Avabruck and Full Moon's Rise) attacking said opponent. Their only blocker was a 2/2, so they blocked.
Curse of Stalked Prey reads "Whenever an opponent is deal combat damage..." and goes on to say the creature that dealt damage gets a +1/+1 counter. Is the counter immediately added, thus saving it from the 2/2 blocker?

Now, if you could give your Trampling Stalking Werewolves First Strike also, you might be in business...  But no, since the werewolf is dealt combat damage at the same time as the opponent, state-based-effects have sent the Waif to the graveyard long before Cruse of Stalked Prey's effect can add a counter.

No, the blocker would be destroyed.  From the comprehensive rules dealing with the Combat Damage Step

510.2. Second, all combat damage that’s been assigned is dealt simultaneously. This turn-based action doesn’t use the stack. No player has the chance to cast spells or activate abilities between the time combat damage is assigned and the time it’s dealt. This is a change from previous rules.
510.3. Third, any abilities that triggered on damage being assigned or dealt go on the stack. (See rule 603, “Handling Triggered Abilities.”)
510.4. Fourth, the active player gets priority. Players may cast spells and activate abilities

The state based action that destroys is 704.5g.  So although the ability triggers it is placed on the stack.  State based actions are dealt with before the stack is, and thus, the blocker dies.

The Curse of Stalked Prey will not save your Reckless Waif.
Because the evaluation of what zone a creature belongs in (has it been dealt lethal damage, does it have zero toughness, etc.) is a state-based action, it occurs before a player would next receive priority.  A player would next receive priority at the end of the combat damage step, which is when the triggered ability of Curse of the Stalked Prey goes on the stack.  See the following from the comp. rules:

704.3. Whenever a player would get priority (see rule 116, "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.
704.5g If a creature has toughness greater than 0, and the total damage marked on it is greater than or equal to its toughness, that creature has been dealt lethal damage and is destroyed. Regeneration can replace this event.

Thus, your creature will go to the graveyard, then the triggered ability that's on the stack will fizzle.

No. The above answers are correct, but they overlook a simple detail: Curse of Stalked Prey only triggers when a creature deals combat damage to a player, not a creature, so you wouldn't get the counter even if your Reckless Waif would have survived combat.

Except that the Reckless Waifs have Trample thanks to Full Moon's Rise.


text:
Creature Ability List
Sudden Spoiling reads

Creatures target player controls become 0/2 and lose all abilities until end of turn.

Can someone help me find a list of abilities that they lose?

From the comp rules glossary:

Text on an object that explains what that object does or can do.
An activated or triggered ability on the stack. This kind of ability is an object.

Every item of rules text in the text box (the box in the lower half of the card) is an ability. Doesn't matter whether it's keywords or full statements; static, triggered, or activated. In addition, lands with a basic land type have an implied ability: "T: Add 1 [color] mana to your mana pool."
In handwavy terms, "lose all abilities" means "pretend there's nothing printed in the card's textbox".
More precisely, you apply effects that add or take away abilities in "timestamp" order. So, for example:

I have a Stampeding Rhino. It has one ability: trample.
I enchant my Rhino with Trollhide. This gives my Rhino a second ability: "1G: Regenerate this creature" (the ability is printed on the Trollhide card, but it as an ability that the card gave to the Rhino).
My opponent plays Turn to Frog on my Rhino, which includes the text "loses all abilities". My Rhino now has no abilities, until end of turn. Both the Rhino's built-in trample and its enchantment-granted regeneration are removed.
After my Rhino is turned into a Frog, I activate Alabaster Mage to give it lifelink until end of turn. Now my Frog has one ability: lifelink.

(Power/toughness-modifying effects are actually a bit trickier, since they are applied in layers. So the Frog is 3/3, not 1/1. That's a different question.)

Alex's answer is quite complete, however his quoted point 2 leaves the impression that an ability on the stack would be affected.  This is incorrect.
From the Gatherer rulings on this card

Sudden Spoiling doesn't counter abilities that have already triggered or been activated. In particular, you can't cast this fast enough to stop a creature's "At the beginning of your upkeep" or "When this creature enters the battlefield" abilities from triggering.

However he's quite correct in pointing out the way that new effects would interact with cards you had already suddenly spoiled :)  It should be clear as well that any creature cast after your Sudden Spoiling would not be affected by it.

Not exactly what you're asking for - as keyworded abilities are only a subset of all abilities, but this page has an up-to-date list of keyword abilities in Magic the Gathering, which you may find fun to peruse:
http://en.wikipedia.org/wiki/List_of_Magic:_The_Gathering_keywords
Having said the above, I don't think you'll ever find a more complete list of abilities that are removed by Sudden Spoiling; as such a list would have to include all the non-flavour-text text written on thousands upon thousands of Magic cards!


text:
Hexproof on an opponent's creature
If I play an enchantment which gives hexproof on an opponent's creature, whose spells is it protected from?  Does it gain protection from my spells because it's his creature, or from his spells because it's my enchantment?

Hi!  Welcome to the site!  For MtG questions its usually better to be specific about the card you are asking about as the there are many different interactions going on and the answer can be different for each.

That depends on how the enchantment is worded.
If the enchantment actually says "Enchanted creature has hexproof", like for example: Alpha Authority, then the enchanted creature will be untargetable by you after the enchantment resolves, but will still be targetable by your opponent. (Note that the creature having hexproof will not cause the enchantment to fall off.) That's because a creature with hexproof cannot be targeted by spells or abilities controlled by anyone other than the creature's controller.
The same applies to equipment such as Mask of Avacyn. (Since you can only equip to creatures you control, this would only be relevant if you had a creature equipped with Mask of Avacyn, and an opponent later took control of this creature.)
If, on the other hand, the enchantment says "Enchanted creature can't be the target of spells or abilities your opponents control," then things are a little different. This enchantment appears to do the same thing, except that in this case "your opponent" refers to the opponent of the enchantment's controller. So it actually has the opposite effect, and allows you to target the creature (since you control the enchantment), but not your opponent.
An example of this is Canopy Cover.


text:
What happens when an undying creature takes damage from a creature with deathtouch?
Let's say a 2/2 creature with deathtouch attacks another 2/2 creature with undying.
As far as I can see there are two ways this could resolve:

Damage is applied, killing creature B. As the damage was enough to kill it deathtouch will not matter. The creature is then put back into play, alive, with a +1/+1 counter.
Damage is applied, killing creature B. It is then put back into play, but with its previous state, i.e. still having deathtouch applied to it, thus killing it and putting it into the graveyard.

I'd be grateful if someone could clear this up for me.

The undying creature will return and stay.
Your provided answer options indicate a misunderstanding of what Deathtouch is. Deathtouch merely says:

702.2. Deathtouch
702.2a Deathtouch is a static ability.
702.2b Any nonzero amount of combat damage assigned to a creature by a source with deathtouch is considered to be lethal damage, regardless of that creature's toughness. See rules 510.1c - d.

In other words:
For normal damage to kill a creature, two conditions have to be true:

The sum of all damage packets on that creature has to be 1 or greater.
The sum of all damage packets on that creature has to match or exceed its current toughness.
If both conditions are met, all damage packets are removed from the creature and it is destroyed.

If any of the damage packets comes from a source with Deathtouch, it merely removes the second condition.
So Deathtouch is not, for example, a triggered ability that would cause another destruction affect on top of lethal damage - there still is only 1 destruction effect.
Going further, your option 1 is closer to the truth than option 2 - if a creature dies and returns, it returns as a new object and (with few exceptions) all spells, abilities, etc. tracking the creature's previous incarnation will have lost track of its new version. So even if the Deathtouch was an effect using the stack, it would still not destroy the returned creature.
Edit:
Thanks to StuartCook, a little correction:
According to

702.2c A creature with toughness greater than 0 that's been dealt damage by a source with deathtouch since the last time state-based actions were checked is destroyed as a state-based action. See rule 704.

the Deathtouch rule comes into effect only immediately after Deathtouch damage has been dealt - if a creature has been indestructible or anything similiar at the time the Deathtouch destruction effect was checked for, but loses that ability later the same turn, Deathtouch damage no longer ignores the creature's actual toughness. It's a one-time effect and for the purposes of destruction becomes regular damage if the creature did not die from it.
It's actually a clever way of keeping the "touch" feel of that ability intact in the rules - once the touch is over (after combat), it no longer kills the target immediately.

Just thought I'd point out that the caveat in your last paragraph is relevant for the few cards which actually say "When [this creature] deals damage to another creature, destroy that creature."  In those cases the triggered ability would lose track of the creature with undying.

Your description of deathtouch's effects is good enough for practical purposes, but it isn't 100% correct according to my understanding of the rules. For example, if an indestructible creature receives damage from a source with deathtouch, and later stops being indestructible, it isn't destroyed, because of the specific wording of 704.5h.

@StuartCook Good point, I tend to agree. If the Deathtouch rule doesn't destroy the permanent immediately, it will not at all.

I don't know the comprehensive rules for this, but from my understanding when the creature returns back to the battlefield it's considered a new object, so the douthtouch that was on it previously wouldn't see it either way since it doesn't know this new object.
It's the same as a creature with undying having an enchantment on it when it dies.  When it dies the enchanment fizzles because it's original creature is gone and it doesn't recognize the "new" one.


text:
Land ratio vs mana curve
When choosing cards for a deck, one of the most important things to consider is the number of land you put in. The biggest issue is mana curve, of course. What shortcuts are best for determining the proper amount of land with a given mana curve?

Issues around how many ETB tapped lands and the issue of colour fixing is just as important than the mere number.

Basically, you're trying to find an optimal balance between "I need mana to play my spells in a timely fashion" and "I want to draw active cards all the time (which usually means spells)."
For me, it boils down to a question of which lands drops do you need to make "on time".
Because players start with an opening hand of several cards but subsequently draw one card per turn (typically), your access to mana isn't linear. On turn 1, you've already seen about 7 cards (and you can mulligan bad hands); making your first land drop is pretty easy even with only a dozen lands in your deck. By turn 4, you've seen only three more cards, so making your fourth land drop (which implies that you also made your first, second, and third ones on time, by the way) reliably now demands that something like 40+% of your deck be land.
It gets even worse for decks trying to stick a six-drop on turn 6: on the face of it, it seems like you'd want over 50% of a deck to be lands! "Real" decks don't do that, though. Instead, decks that top out with some lethal six-drop either play ramp spells or other tricks to get there earlier, or they don't actually fret about resolving one on turn 6 (control decks with cards like Aetherling and Consecrated Sphinx, for instance, are more concerned with getting the mana for timely board control spells, like Supreme Verdict, than actually casting their finisher ASAP).
One important subtlety here is that which cards you need to cast "on time" actually varies depending on your matchup. For example, you might have a combo deck that can reliably "go off" with just two lands, but needs additional mana in order to play counterspells, targeted discard, or redundant combo pieces to overcome disruption. Likewise, in a control mirror, making your land drops is very important, because you need to play a threat and then back it up with your other spells.

As far as general rules of thumb:

Based on the logic above and general consensus among MTG players, a "midrange" deck that relies on its three- and four- drops for heavy lifting should run about 24-25 lands (i.e. 40% lands). 16-17 lands is the equivalent in (40-card) Limited, and is very common. Most of the intro decks WotC prints come with 24 lands.

Low-curve aggressive decks can get away with 20-22 lands. Some can function well on as few as 18-20. The idea here is that, unlike the "typical" deck above, you're only trying to hit your two-drops reliably, and being "mana-flooded" will usually cause a game loss as your deck runs out of steam.

Ramp decks tend to be over 50% mana sources or land-fetching cards, but only 24-26 lands, or even less in environments with super-strong mana acceleration. You can usually cut a land for every two non-land mana sources like Birds of Paradise or Azorius Signet that you play. (Why every two? Because you still need some land to cast your non-land mana sources, and because non-land mana sources are actually pretty pointless unless you're also making your land drops. Also, mana dorks are fragile!) Make sure your accelerators are low enough on your curve that they actually accelerate you, also — for example, Pristine Talisman can help set up Elesh Norn and Gideon Jura, but it's pointless to put one in a deck that's all about Hero of Bladehold or Runechanter's Pike.

Control decks generally run 24-28 lands, with card-draw and card-filtering to help them hit land drops. Low-cost card-draw or card-filtering cards, like Preordain, are kinda like mana dorks for land-count purposes — you'll see more cards, so you can afford to put fewer lands in the deck.

Look at mana requirements other than casting spells, as well. For instance, a deck with Ulvenwald Tracker benefits from being able to cast big dudes and have them fight your opponent's creatures on the same turn, so it might want more lands than a deck with an equivalent casting-cost curve but no mana-intensive activated abilities.

Decks for formats with super-efficient spells, like Legacy and Vintage, tend to run fewer lands than the numbers given above. You could reasonably see a 16-land aggro deck or a 23-land control deck in Legacy, for example.

When available, lands that do stuff other than just tap for mana are a great way to get more "action" in your deck without going land-light. Examples range from Karakas in Legacy, to manlands (like Mutavault) everywhere they're legal, to Teetering Peaks in budget red decks. I've won several games thanks to the relatively minor secondary ability of Minamo, School at Water's Edge.

Once your deck starts doing things with land cards other than tapping them for 1 mana each, the shorthand doesn't work. Two diametrically opposed examples here: Loam Assault is a deck that curves out at 3, but it plays around 28 lands because the goal is to hit the right mana to cast Seismic Assault, and then pitch your remaining lands to it (recycling with Life from the Loam); Green Tron decks play cards like Karn Liberated and Emrakul, the Aeons Torn but only run about 18-20 lands because they can make 7 mana off of three lands and are absolutely overloaded on land search and cantrips.

Though the option is rarely exercised, don't forget that you can side lands in and out. Usually this is done when there are important utility lands that a deck might want to play. If you have the lands in your sideboard already, you can use them to alter your land count in order to match which spells are most time-critical for a specific matchup.
For example, during the Innistrad and Return to Ravnica Standard seasons, some control decks would keep an extra Nephalia Drownyard or two in their sideboard. Drownyard was widely regarded as "the most powerful card in the control mirror, but playing too many lands put you at risk of mana flood against faster decks; having a lot of lands wasn't nearly as bad against other control decks because you got a huge advantage out of being able to play around Mana Leak, win a counter war, pay for a massive draw spell, or activate more Drownyards than your opponent.

If your deck is truly weird, you'll need to throw all conventions out the window and figure it out from scratch. For examples of these, look up Dredge (note the variety of land counts within one archetype, based on cardpool differences!), Belcher, and Legacy Lands.

Most of the suggestions above apply to non-60-card decks as well. Thus, a typical Limited deck will have 17-18 lands and a typical EDH deck will have 38-40, for instance. Additionally,

In Limited, if you don't have enough playables, it's okay to just go heavy on basic lands — at least you'll avoid mana screw. I usually end up playing 17-18 lands even in low-curve aggressive decks because I'll only have about 22-23 cards I'll actively want to run (sorry, Diregraf Escort!).
In EDH, decks of all colors have ample access to "mana rocks" (e.g., most notably, Sol Ring), and even aggressive decks tend to play cards that cost 6 mana or more. In some ways, nearly every deck is a little bit of a ramp deck.

About putting one extra land card and playing a 61 card deck, I would say that this is almost never a good idea. To be able to differentiate the probabilities of a 25/60 (lands/total cards), a 26/61 and a 26/60 deck would require playing a huge amount of games and be very precise keeping track of the lands you get in each game. If you notice a difference in those cases, it's more likely to be caused by chance or cognitive bias.

@Pablo It's the same level of cognitive bias as choosing 25 or 26 lands from the get-go. ;)

@Alex no not really. If your deck is so dependent on all 35 spells and all 26 land that you need to push to 61 cards, then your deck is too fragile for consideration. Compromising to 61 cards is, I would go so far to say, never a good strategy, and most certainly never a good strategy for new players. Teaching players to avoid making the tough decision of what to cut leads to bad decks.

For what it's worth, a 25 land 60 card deck is  41.7% land, 26 land 60 card is 43.3%, and 26 land 61 card is 42.6%. I'm not sure why people think that only the first two ratios can be the best, or that if the third ratio (between the first two) is best it means the deck is fragile.

@Jefromi It's not the ratio itself, it's the way the extra card impacts your odds of drawing your four-ofs.

@AlexP Yes, and 60 vs 61 is not a huge effect there, so I'm sure there are some decks where fixing the mana curve is worth very very slightly decreasing odds of the four-ofs. Obviously in general one should just stick to 60 cards, but it just irks me to see people saying never, or suggesting that you can tell the difference between 25 and 26 but not 60 and 61.

Some can function well on as few as 16-20 For some aggresive decks, you can go down to 12 lands.

@大师燈XiHuan, Hell, Vintage Manaless Dredge runs 4x Bazaar of Baghdad with no other lands in the deck, and Legacy Belcher frequently runs 0-2 lands depending on the specific build. But Alex is talking about rules of thumb, not edge cases.

@Jefromi: My observation is that when you don't say never, players tend to think they are the exception "You said it sometimes makes sense" is not something you want to hear from anyone without a ton of experience about why they have more than 60 cards. Pros are known for tuning their deck well enough that 61 cards makes sense, but that isn't usually about mana curves but instead about other spells. As a simple example adding a silver bullet to a deck with search without impacting your ratios as much as replacing a card would. But again the vast majority of players aren't there.

@Guvante Fair enough, I guess. I just have this reaction because "this is always the best way" gives me an immediate impression that it's being overly absolute, and can't possibly be completely correct. An honest "it might help in corner cases, but there's no way you're tuning carefully enough" feels more helpful to me. (Also, the distinction between adding a spell and adding a land is kind of an artificial one - adding a land without dropping a spell means keeping one of the desired spells instead of having to replace it with a land.)

@Jefromi: My land comment was because adding a land to a 24 out of 60 card deck increases your land density by 0.9% compared to the usual 1.6%. Similarly adding a non-land reduces it by 0.6%. Neither 0.9% or 0.6% makes a huge difference but adding a card makes at least a 31% improvement in card density. (Actual odds are complex and not included)

The general rule of thumb is about 22 - 24 lands for most 60 card decks. Some decks can get away with less due to low curve (for example one drop zoo) and some may need more depending on the situation. Of course there are always extreme exemptions like char belcher which runs a grand total of one land or manaless dredge which runs none.

Well, to be precise, there are 1-, 2-, and 0- land Belcher decks.

Manaless Dredge runs 4x Bazaar of Baghdad, which is a land. (It may not produce mana, but it's a land.) The list also generally runs Serum Powder, which could produce mana if it ever hit the table, but the Powder is only used to fuel mulligans into Bazaar.

@BrianS You're thinking of vintage dredge, which does play lands. Manaless dredge is a version of dredge in legacy, which does not play lands.

It totally depends on the mana curve in your actual deck. A good starting point is 33-40% lands for most Constructed decks. For Limited, you typically want a little more, 40-45%. That being said, there will of course always be decks that require more or fewer lands, and without testing, a definite number is hard to pin down.

Why more lands in Limited?

Limited decks have a lower overall quality of spells, and the power cards in the deck tend to be more expensive: 4-6 mana instead of 2 or 3. So it's more important to hit the first 4-5 land drops consistently than it is in a low-curve constructed deck. Plus, if you miss land drops early, it's easy to fall behind in board position, and the kinds of cards that let you recover from those situations are in very short supply in Limited. Better to avoid getting behind at all, and drawing enough land is a key component of doing so.

@DavidZaslavsky If you fail to draw gas, though, you also fall behind on board position. That's the perennial struggle. :) I see what you mean, though, from an aggro perspective: most Limited aggro decks are "crappy midrange" by Constructed standards, and run the commensurate amount of lands. Looking at the ramp and control archetypes, though, I think the trend is reversed.


text:
Can an Adaptive Automaton trigger Champion of the Parish's ability?
If I have a Champion of the Parish in play and play an Adaptive Automaton, choosing human, does the Champion's ability activate?
I believe it does since

the declaration of human occurs "as the AA enters the battlefield", not "once the ..."
the declaration takes place immediately and is not stack based (per gatherer ruling)
Champion's affect reads "whenever a Human enters the battlefield"

Thus the AA is a human when it enters the battlefield.
Can anyone clarify this more conclusively?

think i just found a new card for my deck!

@DForck42 If you're using Adaptive Automaton as a Human "lord", note that there are also two actual Human "lords" in Innistrad: Hamlet Captain and Mayor of Avabruck.

@alexp yeah, but they're off-color for my deck.  both of them are also iffy lords.

@AlexP ~@dforck42 Both of them are great in a green/white deck, for example in commander.  At the moment I have a hard time justifying green/white in 60 card standard, but I may change my mind in a few days :)

Adaptive Automaton will enter the battlefield already possessing the chosen creature type, which will trigger Champion of the Parish.
Automaton's first ability is a "replacement effect". Relevant rules are under the heading "Replacement Effects". Relevant excerpts:

614.1. Some continuous effects are replacement effects. Like prevention effects (see rule 615),
     replacement effects apply continuously as events happen—they aren’t locked in ahead of time. Such
     effects watch for a particular event that would happen and completely or partially replace that event
     with a different event. They act like “shields” around whatever they’re affecting.
[...]
614.1c Effects that read “[This permanent] enters the battlefield with . . . ,” “As [this permanent]
     enters the battlefield . . . ,” or “[This permanent] enters the battlefield as . . . ” are replacement
     effects.
[...]
614.6. If an event is replaced, it never happens. A modified event occurs instead, which may in turn
     trigger abilities. Note that the modified event may contain instructions that can’t be carried out, in
     which case the impossible instruction is simply ignored.

For more information about how this interacts with Champion of the Parish, let's look at "Handling Triggered Abilities" -- specifically:

603.6. Trigger events that involve objects changing zones are called “zone-change triggers.” Many
     abilities with zone-change triggers attempt to do something to that object after it changes zones. During resolution, these abilities look for the object in the zone that it moved to. [...]
[...]
603.6b Continuous effects that modify characteristics of a permanent do so the moment the
     permanent is on the battlefield (and not before then). The permanent is never on the battlefield
     with its unmodified characteristics. Continuous effects don’t apply before the permanent is on
     the battlefield, however (see rule 603.6e).
Example: If an effect reads “All lands are creatures” and a land card is played, the
  effect makes the land card into a creature the moment it enters the battlefield, so it
  would trigger abilities that trigger when a creature enters the battlefield. Conversely, if
  an effect reads “All creatures lose all abilities” and a creature card with an enters-the-
  battlefield triggered ability enters the battlefield, that effect will cause it to lose its
  abilities the moment it enters the battlefield, so the enters-the-battlefield ability won’t
  trigger.

So, in essence, "As Adaptive Automaton enters the battlefield, choose a creature type"  replaces the normal "~ enters the battlefield" action that you perform when summoning a creature with a subtly different action: "~ enters the battlefield and its controller chooses a creature type".
"Adaptive Automaton is the chosen type in addition to its other types" is a static ability just like shroud or flying, so your Automaton is an "Artifact Creature - Human Construct" (or "Construct Human", I suppose, the rules aren't picky) when it enters the battlefield, and this is the type that all triggered abilities (like Champion's) will see.
If you'd like to see an official example of Adaptive Automaton interacting with a Human-enters-the-battlefield ability, look at the Rulings section for Dearly Departed.

The Champion's ability does not activate.
The Automaton's first ability creates a replacement effect that defines what creature type is being referred to by his other two abilities, which are both static effects.  According to the comprehensive rules:

604.2. Static abilities create continuous effects, some of which are prevention effects or replacement effects. These effects are active as
  long as the permanent with the ability remains on the battlefield and
  has the ability, or as long as the object with the ability remains in
  the appropriate zone, as described in rule 112.6.

This means that in order for the Automaton's static abilities to be in effect, it must be a permanent on the battlefield.  As it's entering the battlefield, it's not yet a permanent, so it's not yet a human, so the Champion won't trigger.
EDIT:
Further discussion has revealed that I am incorrect.  Please refer to AlexP's answer and the comments on this answer for more info.

From the very moment it becomes a permanent, the card's own static abilities apply.

@AlexP Yes, but since a permanent is defined as "a card or token on the battlefield," (110.1) it doesn't become a permanent until after it has entered the battlefield.

See 603.6b (especially the example) and 603.6d ("Normally, objects that exist immediately after an event are checked to see if the event matched any trigger conditions. Continuous effects that exist at that time are used to determine
what the trigger conditions are and what the objects involved in the event look like.")

@AlexP You're absolutely right. Guess I didn't look far enough for confirmation when writing my answer. +1 to you.


text:
When two card texts confict, which takes priority?
Let's suppose there are creatures in play and someone plays Humility.
It's clear that all the creatures lose their abilities.
How is this situation changed if True Conviction were in play?  Is the situation changed if True Conviction were played after Humility?
Is the solution to this question that the card with the newest time stamp is in effect?

How is this situation changed if True Conviction were in play?

It doesn't.

Is the situation changed if True Conviction were played after Humility?

Yes. Each creature of the controller of True Conviction will be a 1/1 creature with Lifelink and Double Strike.

Is the solution to this question that the card with the newest time stamp is in effect?

Yes. Section 613. Interaction of Continuous Effects of the Magic Comprehensive rules describes the order continuous effects are applied.

613. Interaction of Continuous Effects
613.1. The values of an object's characteristics are determined by starting with the actual object. For a card, that means the values of the characteristics printed on that card. For a token or a copy of a spell or card, that means the values of the characteristics defined by the effect that created it. Then all applicable continuous effects are applied in a series of layers in the following order:
613.1a Layer 1: Copy effects are applied. See rule 706, "Copying Objects."
613.1b Layer 2: Control-changing effects are applied.
613.1c Layer 3: Text-changing effects are applied. See rule 612, "Text-Changing Effects."
613.1d Layer 4: Type-changing effects are applied. These include effects that change an object's card type, subtype, and/or supertype.
613.1e Layer 5: Color-changing effects are applied.
613.1f Layer 6: Ability-adding and ability-removing effects are applied.
613.1g Layer 7: Power- and/or toughness-changing effects are applied.

Humility is an ability-removing and power/toughness changing effect. True Conviction is an ability adding effect. Since both effects use the same layer 6 and aren't dependent upon one another, the order the effects are applied is done in timestamp order.
Also note

613.5. If an effect should be applied in different layers and/or sublayers, the parts of the effect each apply in their appropriate ones. If an effect starts to apply in one layer and/or sublayer, it will continue to be applied to the same set of objects in each other applicable layer and/or sublayer, even if the ability generating the effect is removed during this process.

So the power changing effect of Humility will always be applied last, no matter what.

The power changing effects of Humility aren't always applied last.  613.3 expands upon Layer 7.  There are 3 possible effects applied after P/T setting effects.


text:
How does the double strike mechanic interact with other mechanics like lifelink or trample?
I understand that the double strike mechanic allows a creature to attack in both a first strike combat damage step and a normal combat damage step.
It's clear that when a creature with no other abilities aside from double strike is blocked that even if the defender has lethal damage marked in the first strike step that the additional damage does not carry forward to the player.
How does this view of double strike change with relation to trample and lifelink?
I believe the correct interpretations are (not accounting for other effects or abilities) that 2 times the attacker's power is marked as damage on the defender.  For trample this amount is reduced by the defender's toughness and additional damage carries forward as normal.  Similarly for lifelink the active player gains life equal to 2 times the attacker's power.
Thus a 10/10 trampling double striking life linker blocked by a 1/1 creature would deal 19 points of trample damage and the active player would gain 20 life.
Is this interpretation correct?

I think the answer to this is actually not as complicated as first appears.  (I'm assuming you  aren't confused about what happens when a trampling, lifelink creature without double strike gets blocked.)  It all hinges off the following simple (ish) rule for resolving trample:

702.18c If an attacking creature with trample is blocked, but there are no creatures blocking it when damage is assigned, all its damage
  is assigned to the player or planeswalker it's attacking.

Recall that a double striker deals damage in both the first strike combat damage step, and the normal combat damage step.  Now, it may very well be that the blocking creature was dealt lethal damage in the first strike combat damage (and some trample damage may additionally have carried over to the defending player).  In this case,  the blocker is in the graveyard by the time of the normal combat damage step, but, crucially, this doesn't mean that this damage step doesn't happen.
If the double striker didn't have trample, then the normal combat damage step would be basically irrelevant: the double striker still counts as having been blocked, and blocked creatures deal no damage to the defending player. ETA: Additionally, the dead blocker is no longer in combat to take more damage (which may be important if the attacking creature had lifelink). However, tramplers can deal damage to defending players; in fact, any amount of damage that isn't "soaked up" by a defending creature.  Which in this case is all the damage dealt in the normal combat damage step, as the defending creature isn't around to soak up anything.  As suggested by Rule 702.18c.
The lifelink is a bit of a side issue, I feel: it doesn't change anything in regards to the double strike or trample.   It just gives an equal amount of life to the creature's controller to the damage that creature deals, in either combat damage step, and whether that damage is to a blocking creature or a defending player!
So, yes, your interpretation is ultimately correct, I'd say!

With regards to lifelink, your answer seems to assume lifelink and trample. What happens if a doublestrike creature has lifelink, but not trample, and kills the blocker on the first strike combat step? Damage does not go to the player without trample (the attacker is still blocked), but does it still deal damage that triggers lifelink, even though the blocker is already in the graveyard?

@Beofett: no, it does not.

@DavidZaslavsky I thought not. That should be included in the answer, I think, since the question speculates that doublestrike with lifelink should result in simply multiplying the attacker's power by 2 to determine life gained.

I think that info is included in the answer, though perhaps it wasn't sufficiently clearly stated: see the para beginning if "the double striker didn't have trample...".  Blocked creatures deal no damage to the defending player, and "the double striker still counts as having been blocked", even though the defender is now dead and in the graveyard.  Oh, I guess I should have specified that no more damage is dealt to the dead blocking creature!  I'll edit the answer accordingly.

One nitpick: the creature may still be around on the second strike. Let's say the 10/10 FS LL Trample was blocked by a 1/1 indestructible. In the FS damage phase, 1 damage is marked on the 1/1 to assign it lethal damage, and 9 trample damage is assigned to defending player. In the regular combat phase, 0 damage is marked on the 1/1 because it already has lethal damage. This allows for 10 damage on the defending player. (Note that you could, if you wanted, assign more than lethal damage to the creature. You simply aren't required to.) So it's up to 9 and up to 10 damage to defending player.

@corsiKa, When you say "assign more than lethal damage to the creature", does it mean that if I attack a player with a 10/10 and he blocks with a 1/1, I can actually choose not to assign 9 damage to the player? I can assign e.g. 5 damage to the creature and 5 to the player?

@Pacerier That's correct. From the comp rules, 702.19b The controller of an attacking creature with trample first assigns damage to the creature(s) blocking it. Once all those blocking creatures are assigned lethal damage, any remaining damage is assigned as its controller chooses among those blocking creatures and the player or planeswalker the creature is attacking. Now it doesn't usually make much sense to do so, since at this point in time it can't be responded to, but sometimes it does for example preventing your opponent from entering Fateful Hour or something weird like that?

Assuming ETA means edited to add, which makes sense looking at edit history tho doesn't date terribly well 4 years later reading this answer;)


text:
What ways are there for a Standard Werewolf deck to handle Ratchet Bomb?
What can a Standard (M12, Scars, Innistrad) Red-Green werewolf deck use, either in the main deck or the sideboard, to handle a deck with Ratchet Bomb?
Some back story: When a werewolf is in its transformed state, its CMC is 0.  So an opponent can cast Ratchet Bomb, then tap and sac it for 0 and destroy anything with a CMC of 0, which hits all transformed permanents (and all non-land 0 cost permanents).

The tokens deck has the same problem, but worse.

Also, a flipped werewolf has a CMC of 0? For most purposes, a flipped card is considered the same game object as an unflipped card, so I'm very surprised to hear that the CMC changes.

Actually the tokens aren't that bad. Usually you are getting more than a single creature from each spell, plus you have to spend a turn not playing spells to make the werewolves flip. The werewolves require more investment.

@JSBᾶngs The flipped side has its own separate creature types, power and toughness, and color.  It may be the same game object, but it has none of the same characteristics - and sure enough, the comprehensive rules specifically indicate that the back face doesn't have a mana cost (and thus its effective CMC is 0).  See rule 711.2b (and 202.3a) in the comprehensive rules.

@rahzark You can cheat with Moonmist. Also draw-go decks have to change how they play spells in order to keep you from transforming (although arguable that's only in the early game). Tokens can get multiple tokens per card, but Glissa or Sun Titan recurring Ratchet Bomb is just a nightmare for you. I definitely think W/B/(g) Tokens is going to be a "real" deck and Werewolves isn't, though.

It's also important to note that the INN transform cards are not "flip" cards -- those are from kamigawa and have different rules.

Note that as of Shadows over Innistrad the CMC of the back face of a card is no longer necessarily 0.

On color
Green:

The obvious choice in your situation is Full Moon's Rise.  It buffs all your werewolves while it's in play and you can sacrifice it to save all of them from a Ratchet Bomb.
Another direction is Withstand Death, but this only provides the means to save creatures on an individual basis and is a sideboard card at best.
Asceticism gives you the option of regenerating creatures and hexproof on top of that.  However, regenerating a large number of werewolves could get expensive.

Artifacts:

Phyrexian Revoker is another great way to ruin Ratchet Bomb's day, but it has its own limitations and weaknesses as a creature.
Sundial of the Infinite would work as long as they are trying activating the Ratchet Bomb on your turn.

Off color
For others who might have the same concerns in a different mana base.
Blue:  Obviously any counter is going to prevent Ratchet Bomb from ever entering the battlefield.

Steel Sabotage would be a good one specifically for countering Ratchet Bomb.

Black:

Memoricide can remove any Ratchet Bombs that are not in play thus preventing them from ever being used.
Surgical Extraction could be used for a similar effect, but unfortunately can only be used if a Ratchet Bomb is already in the Graveyard.

White:

Stony Silence can prevent the activation of a Ratchet Bomb.
Nevermore can be used to ensure that Ratchet Bomb is never cast.

Don't put all your eggs in the Revoker basket, though: 1 toughness is rather a liability when everyone's running Gut Shot and Geistflame to kill off Delver.

@AlexP - Right.  Like I said, Full Moon's Rise is the obvious choice here.  It's the closest thing to being mainboard viable (even though I would still SB it)

Full Moon's Rise is a card you're likely to run maindeck anyway, so you might as well go to four-of. It also partially protects against sweepers (Immerwolf is still going to die, and if there's a competitive-viable werewolves deck, he's pretty much the centerpiece; also Black Sun's Zenith still wastes you).
W/B Tokens is likely to play Stony Silence in the sideboard to deal with Ratchet Bomb. You could do that as well if you're already splashing white for other reasons.

I'm currently splashing white (via shimmering grottos) to flash back travel preperations, but that'll probalby change with Dark Ascension

Full moon's rise is a good answer. But I'm afraid your point about delaying a turn even though he has removal for ratchet bomb is wrong. I play ratchet bomb, let it resolve. Then play removal in your full moon, you sac in response and I sac the bomb in response.

@AndSoYouCode Good catch. Removed!

This doesn't work at all... Ratchet Bomb will not kill the transformers.
When a flip card flips to it's alternate side, it does NOT become a brand new object. It gains the abilities and stats from the second side, but keeps it's converted mana cost from the face side of the card, as well as it's color, author, etc.
A ratchet bomb would not instantly kill a flipped werewolf. I'm pretty sure they thought that through, as who the hell would want to play a deck that can be countered by one card so harshly?
The card's flip side keeps it converted Mana cost, color, author, etc. when it flips from it's front side. You're good. :-)
709.1c A flip card's color, mana cost, expansion symbol, illustration credit, and legal text don't change if the permanent is flipped. Also, any changes to it by external effects will still apply. <--- From the rule book.

Welcome to B&CG! You've got the right idea looking in the comp rules, but the wrong card type: "flip cards" look like this, with two text boxes upside-down on one side; werewolves are "double-faced cards". See 709.1 and 711.1. (This is annoying terminology. I blame whoever designed flip cards.)

Yup, the distinction is "double faced" cards (cards that have a face on both sides of the card) and "split cards", cards that are split down the middle that rotate (kamigawa block)

Couldn't I Ancient Grudge the ratchet bomb in response to it coming out before its ability goes on the stack? I might be wrong but I thought that it being an instant (and red/green double artifact kill is really a great mainboard card in my opinion.) would beat its ability.

I don't believe you can. Sacrificing the Ratchet Bomb is part of the cost of the ability, which means by the time priority passes to you, the Bomb is no longer there for to Ancient Grudge target.

Any time you try to destroy the Bomb, its controller could activate its ability in response; if you wait until she's already activated the Bomb, it's too late to prevent the ability from going on the stack (also the Bomb sacrifices itself, so there's no permanent in play). Even a split-second card like Krosan Grip can be played around: when your opponent's Ratchet Bomb resolves, she gets priority and can activate it immediately, before you get a chance to lock up the stack with Grip's split-second ability.

This sounds like a great question and you should ask it separately.


text:
What counts as an ability for the purposes of Muraganda Petroglyphs?
Say I control both Muraganda Petroglyphs and Life and Limb - am I correct in assuming that my Forest Saprolings do not get +2/+2 from the Muraganda Petroglyphs, because they have a mana ability?
For reference, they are forests, and rule 305.6 states the following:

305.6. The basic land types are Plains, Island, Swamp, Mountain, and Forest. If an object uses the words "basic land type," it's referring to one of these subtypes. A land with a basic land type has the intrinsic ability "{T}: Add [mana symbol] to your mana pool," even if the text box doesn't actually contain that text or the object has no text box. For Plains, [mana symbol] is {W}; for Islands, {U}; for Swamps, {B}; for Mountains, {R}; and for Forests, {G}. See rule 107.4a. Also see rule 605, "Mana Abilities."

An important note is that as of Innistrad, "[Card] is [color]" is no longer an ability.

Gatherer has the following ruling:

Animated basic lands have mana abilities, so they won't get the bonus.

So your assumption is correct: any land that has become a creature does not get the bonus from  Muraganda Petroglyphs (except in the rare case where the land has lost its mana ability -- and I'm not aware of any card that actually does this).

Altered scope slightly for the question - all the rulings seem relevant now.

Just FYI: There are several cards that make creatures lose all abilities, such as Humility: http://gatherer.wizards.com/Pages/Search/Default.aspx?name=+[lose]+[all]+[abilities]||text=+[lose]+[all]+[abilities]

Any ability text on the card, or any ability granted to the card through an equipment, aura, or other effect would be an ability for the purposes of Muraganda Petroglyphs. In this case the ability is granted by Life and Limb, giving them the basic land type also gives the basic land type's ability of tap for mana.
As a general rule of thumb, if the creature were to have this naturally, would it appear in their text box. Power and toughness effects don't, the creature just has the power and toughness, though abilities that modify power and toughness under certain conditions (when attacking say) do. Supertype, type and subtype don't they are on the type line. Color is set by the cost usually, though it has been ruled that color setting in the text box is no longer an ability. But keywords granted, such as Lifelink and Deathtouch from Basilisk Collar, activated abilities, and triggered abilities granted by outside sources all do count.


text:
Can players tap lands for mana with Enchanted Evening and Grand Abolisher in play?
If I play Enchanted Evening and turn everything into an enchantment, and then play Grand Abolisher to disallow them activating abilities during my turn, can my opponents tap their lands during my turn (say, to make a payment for something)?

Just wondering: are you going to use this interaction to pull some kind of hilarious trick? Because, if you are, I want to know what it is.

No they cannot.
From the rulings on Enchanted Evening:

This has no effect on those permanents other than letting them interact with things that care about enchantments.

Which Grand Abolisher clearly interacts with:

During your turn, your opponents can't cast spells or activate abilities of artifacts, creatures, or enchantments.

I think it's clear that lands have an innate implied ability, even if not printed of "Tap: Add 1 mana of the appropriate colour to your mana pool."
So all we need to know is that this ability is treated like any other:

CR 605.3. Activating an activated mana ability follows the rules for activating any other activated ability (see rule 602.2)

The exceptions listed don't apply to this case because Grand Abolisher is not countering the mana ability, it is preventing it from happening.  Just because it's a mana ability doesn't make it special in this case.

I thought there was a weird exception for mana abilities, but I'm not sure; hence why I asked the question here

@DForck42 Hopefully my edits help clear that up.

DForck42: I think you're thinking of the longago (pre-6th edition) rules about Mana Abilities, which said that they couldn't be countered; IIRC this briefly covered even spells like Dark Ritual.  Those changes are long-since gone, and now things that don't affect mana abilities explicitly say so, but effects like Null Rod's (or Grand Abolisher's, or Linvala's) aren't at all picky.

@StevenStadnicki 605.3b An activated mana ability doesn’t go on the stack, so it can’t be targeted, countered, or
otherwise responded to. Rather, it resolves immediately after it is activated.

@StevenStadnicki Grand Abolisher is preventing activating the activated mana ability per 605.3 but if the ability were activated, it could not be countered per 605.3b

@Stephen D'oh - yes, absolutely you're right here.  I need to get back into the habit of scanning the comp rules again before making proclamations.  Mea culpa. :/  (A big part of the reason that mana abilities don't go on the stack is because they can be played while paying costs for a spell, yes?)

@StevenStadnicki Presumably ... I would even say costs in general (can you prevent a sacrifice to pay costs?  I don't think so but you might be able to prevent an activation before a sacrifice), but it's well beyond my expertise to speculate on design decisions :-)

Back then mana sources and counterspells were interrupt speed rather than instant speed though. I suppose in a way mana sources still are interrupt speed, just nothing else is so they appear to happen immediately!

@AlexP Since it can't be done, whatever the original poster's goal was can't be achieved ... it was clever, just against the rules :)

@Stephen Well, no, the trick would be to prevent them from getting mana and then use that to your advantage (e.g. some weird tax effect?); I don't know why I made my comment a comment on the answer and not the question, though -- oops.