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In plain English, how does casting spells and using creature abilities work with the stack and priority?
I'm a relatively new player to Magic: the Gathering. I was reading the expanded rules to try to understand exactly when it's okay to cast instants (e.g. Cancel) and use some abilities (e.g. Goblin Diplomats should be tappable sometime during other peoples' turns), but I don't seem to be making much progress: as I come to understand some things, others make less sense.
My confusion is boundless
For instance: to cast Instants one needs priority. Spells go on the stack, and priority gets passed at some points (I have no idea when), and effects on the stack are resolved when both players have passed priority. But when is that? I can't find any mention of when the other player gets the priority to cast an instant, except on their own turn. Furthermore, The Complete Turn states that during the Main Phase:

505.4. Second, the active player gets priority. Players may cast spells and activate abilities. The active player may play a land.

So players (plural) may cast spells, but only the active player has priority, so only the active player can cast an instant. The turn rules, and the rules on Casting Spells, never mention any point at which the other player gets priority, so when can they possibly Cancel?
In addition, you can only cast a spell when the stack is empty, so the entire stack must be able to be resolved in your turn at some point.
I need an explanation!
I could go on a bit more. There is also Counterflux which can be overloaded to "Counter each spell you don't control", which seems like it could only possibly work with an understanding of the stack.
Could someone explain, in simple English:

When can Instants be cast?
When can tap abilities be used?
What do Instants and abilities have to do with the Stack and Priority?

If this is too broad, please advise me on how I should split it up! I would be happy to discuss how I should be asking this question in the Magic: the Gathering chat room, too, so if it's going to be a bit involved working out how to ask this, please join me there so we can work on it.

@user1873 I think so too, I'm just not sure exactly how I should split it up.

Your 2nd question is the odd man out, if it was "when can activated abilities be used?" Then the question is entirely about the Stack and Timing and Priority. My guess is that perhaps you haven't seen many Activated Abilities without {Tap} in the cost, or you didn't know the proper name for Activated Abilities.

@user1873 I didn't know the proper name, and until today I didn't fully recognise them as being the same thing: e.g. now I realise they're just like Duskmantle Guildmage's abilities, but with tapping being part of (or all of) the cost.

I am going to reiterate that the Basic Rules are sufficient for and a better way to learn how to play MtG rather than the Comprehensive Rules
When can Instants be cast?
Instants can be cast on your own turn, during your opponents turn, and in response to other spells. This differs from Sorcery cards, which can only be cast during your own Main Phase. (MtG Basic Rules, Page 6)

Instant - An instant is just like a sorcery, except you can cast it just about any time you want, even during your opponent’s turn or in response to another spell. Like a sorcery, an instant has its effect, then you put it into your graveyard.

When can creatures use their abilities, like tap abilities?
Anytime you could cast an Instant. There is nothing inherently different between an activated ability with the tap symbol in its cost and other activated abilities and their costs. Tapping is a cost, and just like any other cost, it must be paid before activating an ability.

Activated Abilities - An activated ability is an ability that you can activate whenever you want, as long as you can pay the cost. [...] Each activated ability has a cost, then a colon (“:”), then an effect. [...] Some activated abilities contain the {T} symbol in their costs. This means that you must tap the permanent to activate the ability. You can’t activate the ability if the permanent is already tapped. (MtG Basic Rules, Page 12)
Creature - [...] Unlike other types of permanents, creatures enter the battlefield with “summoning sickness”: a creature can’t attack, or use an ability that has {T} in its cost, until it has started your turn on the battlefield under your control. You can block with a creature or activate its other abilities no matter how long it’s been on the battlefield.(MtG Basic Rules, Page 6)

What do Instants and abilities have to do with the Stack and Priority?
Instants, Activated Abilities both go on the stack. The stack gives players the opportunity to respond to spells/abilities before they resolve. The stack is a First In Last Out (FILO) zone, where spells and abilities exist until they resolve or are countered. (Instants/Sorcery) spells have their effect and then go to the Graveyard, (Creatures/Enchantments/Artifacts/Planeswalkers) resolve and become permanents on the Battlefield, (Triggered Abilities/Activated Abilities) are not represented by a physical card, so they resolve and disappear into the AEther.
Priority is just the way MtG is designed to handle whose turn it is to do something. Players can cast Instants or activate abilities on other players turns, so the game needs a way to determine who goes first.

The Stack - Spells and abilities exist on the stack. They wait there to resolve until both players choose not to cast any new spells or activate any new abilities. Then the last spell or ability that was put onto the stack resolves, and players get a chance to cast spells and activate abilities again. (You’ll learn more about casting spells and activating abilities in the next section.) This zone is shared by both players.(MtG Basic Rules, Page 8)
Priority - Since players can cast instants and activate abilities during each other’s turns, the game needs a system that makes sure only one player can do something at a time. Priority determines, at any given time, which player can cast a spell or activate an activated ability.
The active player (the player whose turn it is) gets priority at the beginning of each step and each main phase—except for the untap step and the cleanup step. When you get priority, you can cast a spell, activate an activated ability, or pass (choose to do nothing). If you do something, you keep priority, so you make the same choice again. If you pass, your opponent gets priority, so now he or she gets that choice. This goes back and forth until both players pass in a row.
When both players pass in a row, if there’s a spell or ability waiting on the stack, it resolves. Then the active player gets priority again, and the system repeats. When both players pass in a row, if there’s no spell or ability waiting on the stack, that part of the turn ends and the next one begins.(MtG Basic Rules, Page 30)

The thing that confused me about this was I didn't know if "passing" referred to ending your turn or something else (which would mean terrible things about when something like Enlarge would get resolved) - now I understand it's just part of some small process that occurs each time spells and abilities are used (and, I suppose, attacking too). Thank you for this.

@doppelgreener And it's usually treated completely informally. Players don't typically explicitly pass. One player just says they're gonna do a thing, and then the other might say "in response, I do X". Because most of the time it doesn't much matter. But the rules are there in case it does. And it can behoove one to be more explicit if you think it will matter.

Basically, the answer to this question lies in the understanding of the phases of the turn.
there are a number of phases and steps that a turn goes through, here is a brief overview:

Untap step
Upkeep
Draw step
First Main Phase
Combat phase (has many sub steps, skipped for understanding)
Second main phase
End step
Cleanup.

The above is not an exhaustive list, but it gives you enough understanding to get your head around what's going on.
Whoever's turn it is, that player is the Active Player. The other player(s) are Non-Active Players. This terminology will help with explaining things.
The best rule of thumb is "The active player has priority right now." 90% of the game this will be true. and during this time you can't do anything. To clarify a little, Whenever a new phase or step begins, the active player has priority. Think of it this way, the active player moves into their main phase, they have lands to play and spells (including creatures) to cast, and this is where that process all starts.
The next thing to understand is how the stack works. Again, a good rule of thumb is "if something happens, it usually uses the stack". For example, casting a creature uses the stack, activating Olivia Voldaren's ability uses the stack. Casting Oblivion Ring uses the stack, so does it's enter the battlefield trigger (there are numerous answers about these for further information) essentially, anything that doesn't directly generate mana uses the stack. I say directly, because Scalding Tarn's ability will get you mana after it resolves, but it does not generate mana and DOES use the stack.
Here is what happens with the stack:

Someone puts something onto the stack
That player gets priority and could cast additional spells if they wish.
After that player passes priority, each subsequent player gets priority.
After all players pass priority, the object on the stack resolves.

When a player has priority with something on the stack, they can cast instants (or spells with flash)
if someone chooses to cast something with something else on the stack, then the whole process repeats for THAT ITEM until it has resolved, and then steps 2-4 are repeated for the Original item.
let's look at an example:
Albert is in his main phase, he casts Ancestral Recall. Oh no! Nancy is wisely playing islands, and with Counterspell in hand, wants to tap 2 of them to make sure Albert's day is ruined.
Here is how this looks on the stack:
  1. Albert casts Ancestral Recall. Ancestral Recall Goes onto the stack.
     2. Albert wants to do nothing and implicitly (by sitting there doing nothing)
passes priority.
     3. Nancy gains priority and responds with Counterspell.
        4. Nancy gains priority and implicitly passes by doing nothing.
        5. Albert gains priority and, looking smug, says "In response" and slaps his own
Counterspell onto the table. Poor Nancy!

Uh oh, things are getting complicated now! Here's a look at the stack
right now:

Albert's Counterspell

Nancy's Counterspell

Albert's Ancestral Recall

        6. Albert gains priority again, and again silently does nothing.
        7. Nancy doesn't have anything else to do so she disappointedly says "Resolves."
     8. Albert's counterspell resolves.
     9. Nancy's counterspell is removed from the stack, so we skip back down to just
looking at Albert's Ancestral Recall.
  10. Crossing his fingers, Albert passes priority.
  11. Grumpily, Nancy says "Resolves." She has no more answers.
  12. Albert's Ancestral Recall resolves. He cackles maniacally as he
draws 3 additional cards.
This demonstrates how things work with the stack. This passing of priority happens everywhere. If Albert wants to go to the combat phase, he passes priority and Nancy might do something in his main phase. If Albert wants to end his turn, Nancy gets an opportunity to cast some spells before her turn starts.
hopefully this has helped understand the stack, in answer to your bullet points:

Instants can be cast at any point where you have priority, all required targets and no restrictions prevent you casting them (e.g. you can't cast Doom Blade with no creatures on the battlefield, and you can't cast anything after Silence resolves).
Tap abilities can be used any time you can cast an instant, excepting abilities that state otherwise (such as Birthing Pod's). Remember that creature have "summoning sickness" (creatures that you haven't controlled since the beginning of your turn may not activate abilities with the Tap or Untap symbol unless they have haste).
Instants and abilities are put onto the stack to resolve, and can only be placed there by the player who has priority. Hopefully the above has explained when this happens.

Most of the time, priority passing happens fluidly and implicitly. As a result, usually it is enough to know that "in response" means that the spell is still on the stack, and you get to do things if you want at the end of each part of the turn.
Here is an interesting situation with how the stacks and priority work to show how you can't do whatever you want, whenever you want.

Alberta casts Lingering Souls, a powerhouse of a card against Norman's deck, and passes priority.
Norman has a Surgical Extraction in hand and wants to use it to stop the spell being flashed back and clear the other copies away to limit the damage, but the spell is on the stack so he cant exile it yet, he passes priority and the spell resolves.
Norman wants to cast Surgical Extraction, but since the spell resolved, priority reverts to Alberta. He has to wait until Alberta moves to a different phase or casts some other spell to get priority.
Alberta gets greedy and fancies 2 more tokens, she flashes back Lingering Souls straight away. Poor Norman's Surgical Extraction is now a dead card. The Lingering Souls is on the stack and will then be exiled.

There are times where priority has a massive impact, and the above is one of them.

i have tried to keep it simple, but i maybe have used too much depth. i have included summaries but if this is still confusing i can try and clarify. (I cant use chat at my current location, so could not discuss as you suggested)

This is very helpful, thank you. One thing is unclear to me: do both players have the opportunity to cast more than one spell before passing priority?

@JonathanHobbs Yes, because when you cast a spell or activate an ability we'll pass priority again afterward. But, honestly, you almost never want to put multiple things on the stack at once, since you can just wait for the first one to resolve (or for another player to react to it) and then cast your second thing.

Minor nitpick, prompted by the previous comments: Note that the answer is incorrect for casting multiple spells; it says the Active player gets priority after the spell is put on the stack, but according to 601.2h, the player casting the spell retains priority.

@tengfred i did not know that, does that mean that the spell's caster gets priority twice? or is it just inverted? in any case i will update

@Rawrgramming it means that when you cast a spell, you are the first one allowed to respond to it (although it is rare that you would want to do so).

@Rawrgramming As I understand it, it is inverted. The rule still is that if both players pass, the top item of the stack resolves. It mostly matters with spells/abilities that copy spells on the stack; you can not wait to see if the opponent responds before using such abilities. As David_Z says, in the normal case you just pass this priority. In fact, in the Magic online game, the default setting is to always pass prio after casting a spell, unless ctrl is held when casting.

@Rawrgramming I tried to make your formatting match Abby's suggestion here. Please double-check that I didn't mess up the levels.

@AlexP your changes all look good, thanks for the improvements!

I will not answer any of your (somewhat) specific questions, as I feel they would not clear up much of the confusion you seem to be feeling. Instead let me give some general advice.

This document is designed for people who've moved beyond the basics of the Magic: The Gathering(R) game. If you're a beginning Magic(TM) player, you'll probably find these rules intimidating. They're intended to be the ultimate authority for the game, and you won't usually need to refer to them except in specific cases or during competitive games.

That is the first line of the expanded rules that you linked to, and you should not ignore it.
Reading the Comprehensive Rules is a terrible way of learning the basics of the game. Absolutely dreadful. I would have given up on the game long before I've played my first match if I first had to read and understand that brick, even though it was smaller back then. It's like studying quantum chemistry in order to cook a pack of instant noodles. I cannot stress this enough: Don't read the CompRules to learn the game. Only open the CompRules if you have a very specific question and are already familiar with the basic rules.
Instead you have 2 much better options:
Find a group of friendly, experienced players who are willing to play casual games with you, who can explain the basics, point out your mistakes, and let you take back moves, maybe even play with open hands. Or, if you feel more comfortable reading, read the basic rules by WotC.
That's really all there is to say. Don't get ahead of yourself, it will only frustrate you.

I appreciate the advice and warning - I did read that first line of the expanded rules. Our group has already run into some confusion about precisely when an instant can be cast, hence I'm seeking some clarification from the rules. Our newbie (and probably not expanded-rules legal) approach is probably good enough for us to continue with, and I've no intention of diving too deep into the rules, but I do want to understand the process in the events we need the clarity of it.

I think what answers most of your confusion is section 117 of the comprehensive rules, the section on timing and priority. Most specifically the rules that deal with who has priority and how it is passed, 117.3, and how priority passing affects spells and steps of the game, 117.4.

117.3 Which player has priority is determined by the following rules:

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

117.4 If all players pass in succession (that is, if all players pass without taking any actions in between passing), the spell or ability on top of the stack resolves or, if the stack is empty, the phase or step ends.

In plain English:
117.3a and 117.3b: Priority resets to the player who's turn it is when something resolves and as the game proceeds through the turn.
117.3c: After a player with priority casts a spell or activates an ability, putting it on the stack, they keep priority.
117.3d: When the player who has priority decides not to do anything with it, priority passes.
117.4: If everyone passes priority, the last spell or ability put on the stack resolves, or the game moves to the next step of the turn if there's nothing on the stack.


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How does Hour of Devastation's Neheb the Eternal work with extra combat & main phases?
Earlier today @Wizards_MagicEU revealed Neheb, the Eternal. This is a creature card which reads:

At the beginning of your postcombat main phase, add {R} to your mana pool for each 1 life your opponents have lost this turn.

Cards like World at War, Waves of Aggression and Relentless Assault create additional combat phases and main phases which make the turn structure look more like this (assuming you cast just one of them):

Main phase
Combat phase
Main phase
Combat phase
Main phase

Let's assume in every Combat phase, I make my opponents lose some life.
How does Neheb, the Eternal's ability function in this structure? When does he trigger and how much mana does he add each time? I think he'd trigger in every main phase but the first and add a cumulative amount of mana each time; is that accurate?

My only comment is that this will be sliding straight into my Rakdos Lord of Riots Commander Deck :P

Any Main Phase that follows a Combat phase is a "Postcombat Main Phase".

505.1a Only the first main phase of the turn is a precombat main phase. All other main phases are postcombat main phases. This includes
  the second main phase of a turn in which the combat phase has been
  skipped. It is also true of a turn in which an effect has caused an
  additional combat phase and an additional main phase to be created.

So Nehab, The Eternal will trigger for each Main Phase that is not the First Main Phase.
It's also worth noting that the mana added is based on cumulative life lost by opponents during this turn. Any life lost prior to this triggered ability's resolution adds {R} to the mana added to your mana pool.

Adding to Nathan Hase's answer, the life lost (and respectively, red mana added) is an absolute value at any time. What you're doing is basically checking the amount of life lost every time the abilily resolves, no matter what else happened this turn.
Let's have an example turn with Neheb, the Eternal already on the board:

In your precombat Main Phase, you only cast Rift Bolt, dealing 3 damage to your opponent. In the Combat Phase, you attack with Neheb, the Eternal, dealing another 4 damage, and cast a Lightning Bolt for another 3 damage.
In your post-combat Main Phase, its ability triggers, adding 10 red mana to your mana pool (because that's how much life your opponents lost this turn). You choose to spend some of that to cast Waves of Aggression (the unused mana empties from your mana pool at the end of the phase).
Following that Main Phase, there's an additional Combat Phase, in which you again choose to attack with Neheb, the Eternal, dealing another four damage. In the Main Phase following that Combat Phase, the ability triggers to add 14 red mana to your mana pool.

For the sake of easier reviewability, let's display this example in a more compact manner:
phase          | damage dealt | mana produced
---------------|--------------|--------------
Main Phase 1   | 3            |
Combat Phase 1 | 4+3          |
Main Phase 2   |              | 10
Combat Phase 2 | 4            |
Main Phase 3   |              | 14

Neheb, the Eternal + Aggravated Assault + 5 damage = infinite combat + untaps. Can't wait to put this in my Kiki-Jiki, Mirror Breaker commander deck

source: Stack Exchange

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

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Can I look up a large list of cards on MagicCardMarket.eu?
MagicCardMarket.eu is apparently the go-to store for buying Magic cards in Europe, and I'm using it for the first time. I've a list of cards I'd like to buy to finalise a deck, and I can't find any way to search for them except one by one.
Other card sellers I was used to using in another country let me input my entire want list and search for all those cards at once -- and it'd make suggestions for each one. I gather I can set up a want list so that sellers can contact me, but that's an advertising mecahnism, not a search mechanism — I want to search for all cards on a list I've got.

I'm not really sure if this is on-topic or would be considered off-topic for Board & Card games. It kind of makes sense for it to be posted here but I haven't seen anything similar to it before for MTG. I posted a question on the meta if you think it should be discussed further.

@Malco Thanks for the invitation to respond to that. I'll follow that up.

Thanks to JonTheMon in chat I've been able to find out how to get to this feature. It's a registration-only feature hidden behind another feature.
The basic steps are: register → set up a wants list → via that wants list, enter the shopping wizard.
The detailed steps

Register an account. You can't access the feature anonymously yet.
Once your account is registered and verified, mouse over the Buying menu and pick My Wants from the dropdown.
Once on the Wants screen you'll see nothing other than the option to create a "new list" with a single input. This input will be used to name the list itself:

Enter the name of your list here and hit the plus button. In my case I named the list after the deck I was buying cards for, and called it "hapatra wants". You can set up other Want lists later, or delete them.
Once your list is created you'll see the screen below. Hit Add Deck List for mass adding:

Enter your cards in the 1x Card name format and hit the plus when you want to add them:

You'll see a confirmation below, and can hit the small "back to your wants list" button at the bottom:

Now that your wants list is set up, you can hit Shopping Wizard:

From the shopping list you can configure how you want to search, and it'll produce one or more batches of cards from sellers matching your criteria.

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


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Forbidden Desert: Valid Navigator and Climber combo to save two buried players for one action?
In the game Forbidden Desert, players can be buried when there are too many sand counters on their location.  Tiles with more than one sand counter on them are considered blocked.
The Navigator can move any other player up to three spaces during his turn by spending one of his actions.
The Climber can move through blocked tiles, and can bring one player with her as she moves.  Players on the same tile as the Climber, including the Climber, are never buried.
Let's say that the Climber is on the same spot as two other players, the tile they're on has a gazillion sand tokens, the Navigator is on another spot in the board, and it's the Navigator's turn.
Example: Each matching pair of square brackets represents a tile, and the players on the tile are listed inside.  The letter in parentheses indicates the name of the tile (used only for naming purposes).  The number of "SAND" words in curly brackets indicates the number of sand tokens.
[(A) Navigator] [(B) ] [(C) Climber, Archaeologist, Meteorologist {SAND, SAND, SAND}] ...

Can the following combo be achieved for one action point from the Navigator?

Navigator uses up one action point to move another player, and chooses to move the Climber for up to three unblocked spaces.
For the first space, Navigator moves Climber from (C) to (B) (Right to left, i.e. <<==).  Climber brings the Archaeologist with her.
For the second space, Navigator moves Cliimber from (B) to (C) (Left to right, i.e. ==>>).  Climber leaves the Archaelogist on tile (B).
For the third space, Navigator moves Climber from (C) to (B) (Right to left, i.e. <<==).  Climber brings the Meteorologist with her.

For one action, Navigator has rescued all the people from the blocked tile using the Climber's person-carrying abilities.
Is this combo legal?

I don't have my game/rules with me, but I don't think that is a legal combination.
My understanding is that the Climber can take someone with him, but that someone would have to go with him for his entire move (on that particular action). So he would not be able to pick up another player in the middle of his movement.
If the Climber were using his own actions, each tile is a new action so he can pick up or drop off as he chooses. but if using a single action given by the Navigator, I think all three tiles would have to include the same set of player tokens.
This is the way I have played. I'll have to double check my rules to see if there is any clarification.
(And I assume this is your question on boardgamegeek).

The rules specifically state that the Climber "may" take 1 other player with her when she "moves," which I take to mean that it's the Climber's prerogative whether or not she takes anyone "when she moves," so I would say, "Yes," the combination is valid.

The Navigator moved another player (the Climber) up to 3 unblocked (for the Climber anyway) tiles per Navigator's action.
The Climber took 1 other player with her when she moved.  (The spirit of the Climber seems to be an ability to tether a non-Climber to the Climber -- possibly with a quick-release D-ring. I can see how the Climber simply untethered (no action) the Archaeologist, went back for the Meteorologist, quickly tethered (no action), and delivered the Meteorologist to safety.

Very clever indeed!

Climber: He may also take
one other player with him whenever he moves.
Navigator: The Navigator may move another player up to 3
unblocked tiles per action, including tunnels.
The Navigators power is to move a player.  This may be up to three spaces.  If the word move is to mean a single journey then I would say no, the two are not saved.  If on the other hand it is a series of steps then it is OK to do so.  The rules do not cover this usage well enough to be clear about it.  My guess is no.  With this kind of usage the Navigators power can also be used throughout the turn in 1-3 tile steps.
Ex: Act 1a: Via the Navigators power) Move Climber to Well one tile. Act 2: Navigator meets climber (1 move). Act 3: Navigator reveals well. Act 1b: Move Climber and Navigator to Tunnel (second Climber tile move).  Act 4: Navigator clears one sand.   1c: Move Climber to another tunnel.
In my mind the rule: Climber: He may also take
one other player with him whenever he moves.  Is a point A to point B reference like the jet pack, which should not allow for the complete redistribution of the players.

According to "Three questions i ask Matt Leacock(Game Designer)" (https://www.boardgamegeek.com/thread/1412989/three-questions-i-ask-matt-leacockgame-designer), this is allowed:

So lets say there are two people on a blocked tile [a] and climber on unblocked tile [b] and the navigator is on [c] also unblocked. On the Navigators turn, he can move the climber 3 spaces for 1 action. So can he move the climber to the blocked tile [a] pick up a guy, move back to [b] drop off that guy and then move back to [a] essentially making both of those players now on unblocked tiles? all in 1 action of the navigator?
Yes. That's fine -- nothing prevents it.

Emphasis added

That's not the question, the question is about switching who is moving in the the middle of the 3 space move.

@bwarner - Actually, the link shows the full situation described is allowed. I've proposed an edit (grr for not having enough rep on this site to unilaterally make them). Any chance you could approve and then ping me? (I downvoted before following the link, but now can't change to an upvote until someone approves my edit....)

That link isn't super authoritative.  It basically says "I asked this question and here's the answer I got".  It is much better to have an answer where the designer answers with their own account.  As is I feel like this is just another opinion.


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What does "each other player" mean on Unwinding Clock?
If I am playing a four man free for all, when do my artifacts untap using Unwinding Clock's ability? I'm having trouble understanding. The card says "each other player". If I am player one, are players two three and four "other players" or is player three the other player since it says "each other player"?

Why would player three be the only player referred to by "each other player"?

@Joe See my answer - I was confused too, but my wife figured it out for me!

@Joe, the OP seems to have confused "each other" (each player other than you) with the English phrase "every other" (which can refer to skipping half of the objects in the set)

You untap your artifacts during player two's untap step, player three's untap step, and player four's untap step.
This isn't anything that's in the comprehensive rules or anything, it's just the meaning of the words on the card. "Each other player" could be explained as "each player who is not you" or to be really clear "every single player who is not you". None of those players is you, so you untap your artifacts during each of their untap steps.
I think you might have been wondering whether "each other" meant alternating (yes 1, no 2, yes 3, no 4...) like "every other" sometimes does. But "each other" doesn't ever mean that, so there's no ambiguity here!
You can see this demonstrated indirectly a few places in the rules, for example:

103.4. ... First, the starting player declares whether or not he or she
  will take a mulligan. Then each other player in turn order does the same. ...

Obviously that applies to all players, not alternating players! And of course, all the cards that say "each other player" wouldn't really make much sense if they meant alternating starting with you - in a two player game, that'd be just you.

Each other player always means every player that is not yourself, not to be confused with alternating players. I've not come across a card that says this but I think this is what is confusing you?
Cards usually use each other player to signal every opponent http://gatherer.wizards.com/Pages/Card/Details.aspx?name=grave+pact, and target opponent to signal just one opponent. http://gatherer.wizards.com/Pages/Card/Details.aspx?multiverseid=227064

In a two-headed giant game, "each other player" does not mean the same thing as "each opponent". They are worded differently for a reason.

Also, your explanation could be a lot clearer - "every other" often means "alternating" in everyday English.


text:
Does Soul Link give life twice in combat and fighting?
Soul Link says:

Enchant Creature
Whenever enchanted creature deals damage, you gain that much life.
Whenever enchanted creature is dealt damage, you gain that much life.

If the enchanted creature is blocking, does the player gain life from the both the dealing of damage and the takng of damage at the same time?  I would think so since damage is dealt simulateously and there is no reference to "either/or" in the oracle text.

Yes, you are correct. When damage is dealt, 2 separate triggered abilities trigger. You will choose the order in which to put them on the stack, and then each one will resolve.
An example: Your Soul Link is enchanting a 3/3 creature, which is blocking a 1/1 attacker. When damage is dealt, your creature will deal 3 damage, and be dealt 1 damage. 2 abilities will trigger: "gain 3 life" and "gain 1 life". You will put them both on the stack, and get a total of 4 life.

Note that you don't actually gain the life at the same time as the OP said - it's two separate triggers. But that's pretty unlikely to matter.

Oh, never mind, the "at the same time" was probably referring to the damage, not the lifegain!

Angel of Vitality is an example where it does matter. Since there are two triggers you get two additional life points instead of one.

@Fax There's about 20 cards that care about life triggers and not amount of life, Archangel of Thune, Ajani's Pridemate, Bloodthirsty Aerialist and Karlov of the Ghost Council are the most notable.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
Can Ink Treader Nephilim's Electrolyze copies target players?
I am curious if the Electrolyze copies created by targeting Ink-Treader Nephilim can be aimed at players for 1 point of damage or if all the damage must go to the creatures that Inky specifies the copies must target.
I have reason to believe no based on the wording of cards like Wild Ricochet, where it specifies on WR that you can pick new targets.
This sort of question also applies to cards like Liquid Fire and Arc Lightning.

No, you cannot, because the card specifically states that each copy targets "one of those creatures." So the target for the copy is specified in the rules of the card itself, there is no option to choose a different target.
Arc Lightning is the same, but Liquid Fire works a little differently. With liquid fire, there is only one target, the creature. How much damage is done to the creature vs the creature's controller is chosen as you cast the original Liquid Fire, and that same chosen number will be applied to the copies. (By rule Rule 706.10). So if you chose "x = 0", thus dealing 0 damage to  Ink-Treader Nephilim, and 5 to  Ink-Treader Nephilim's controller, then 0 damage will be dealt to each creature, and 5 to each creature's controller. (So players who control multiple creatures will take 5 damage for each creature they control, not just 5 damage total).

Indeed not mechanically, but flavourfully you can with Form of the Squirrel.

all_licenses: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/


text:
Can my opponent really have no benched pokemon, even with a Pyroar?
My opponent has a Pyroar and when it's in play he doesn't place any other pokemon on his bench so I can't have him switch out. Is that allowed?

Yes.   The rules only require that the player have one Pokemon in the active position.   Pokemon on the bench are optional.   If the opponents active Pokemon is knocked out, and they have no pokemon on the bench to replace it, the attacking player wins.
Pyroar has an ability, Intimidating Mane,  which reads
"Prevent all damage done to this Pokémon by attacks from your opponent's Basic Pokémon."
It is up to you to build a deck that includes an appropriate counter to the opponents Pyroar.   This could be Rayquaza's Shred attack, Golurk's Devolution Punch, Staraptor's Strong Breeze, or any other pokemon who's attack reads "This attack's damage isn't affected by any effects on the Defending Pokémon"
Or you can evolve a Stage 1 or 2 Pokemon, or Mega EX Pokemon, who's attacks aren't blocked by Pyroar's ability.
Good Luck


text:
Can I use tokens and basic lands from outside my format?
This may sound like a noob question but I cannot find answer anywhere and I still learning all new stuff since I last played so I will ask here.
What does the rules say about using non-format tokens and basic lands in specific format tournament?
Example: I want to play token deck in standard tournament but I don't have current standard tokens/basic lands, can I use previous release tokens if they are the same in stats, types, etc?

Yes. If a card (e.g. "Island") is allowed in the current format, you may place any print of that card into your deck.
You can even use a print of a card whose text has since been changed in Oracle. The text in Oracle always overrides the text on the card.
The cards much match the following criteria:

The card is genuine and published by Wizards of the Coast
The card has a standard Magic back or is a double faced card.
The card does not have squared corners
The card has black or white borders
The card is not a token card
The card is not damaged or modified in a way that might make it marked
The card is otherwise legal for the tournament as defined by the format
The card is a proxy issued by the judge of a tournament

(See section 3.3 of the Tournament Rules for a couple of additional notes.)
Note that wear and faded ink on older cards could be construed as markings. Sleeves can address these issues.
As for tokens, you can use anything that can be tapped. You can use an Ace of Clubs as your Spirit token if you so desire.

I've even seen token starved folks use dice for their tokens (sometimes a 6 means a 6/6, other times a 6 means 6 of whatever token it represents...), with their position representing tapped vs untapped vs summoning sickness. I don't recommend it because it forces you to remember so much more, but it does work in a pinch.

@corsiKa, A despicable practice, in my opinion. Use the face-down cards of another deck instead.

If your opponent wishes to use dice for tokens (I do so frequently, myself) and you do not feel their use is clear enough, you can request they use something more clear to represent the tokens. Tokens can be anything so long as their state is clear to everyone participating in the game.

Face down cards from another Magic deck can appear to be face-down morph creatures.  Also, even in block constructed, a dedicated token deck can generate hundreds of tokens.  I typically use 3 10-sided dice placed atop a single token card to represent numbers of that token from 001 to 999.  If I split them (tap some without tapping others) I'll ask my opponent if he wants me to write the number of tapped and untapped on a piece of pocket notebook paper and leave it by the token until they untap.

@gather818, Re "Face down cards from another Magic deck can appear to be face-down morph creatures." Still way better than dice, even though it's a made-up problem. You can take the sleeves off.

@gathere818, Re "a dedicated token deck can generate hundreds of tokens", So put dice on a token (which I see you went on to mention.) It's just dice alone that's a problem. Too hard to see and read. You can use two cards and two sets of dice if you have some tapped some not.

You can use any black- or white-bordered version of any card that is legal in your format, including basic lands. For example, Naturalize was printed in Magic 2015, so it is standard legal, but you can also use your Onslaught Naturalize and it will be perfectly legal.
Tokens are not considered Magic cards by tournaments: they don't go in your deck, or in your deck list. You can use any object you want to represent a token, as long as your opponent knows what it's supposed to represent (and, in most cases, you should be able to indicate that it's tapped).

Thanks much! I am still new and just starting to gather my new collection but it will help me for sure to look for some specific cards :)

For whoever is interested, "You should be able to indicate that it's tapped" is covered by section 1.10 of the Tournament Rules. It's worded differently, like "Players must maintain a clear game state." Being tapped happens to be a part of the game state.


text:
How to approach a game of Othello / Reversi?
I have played the game Othello (Reversi) numerous times but I never approach it with a specific logic or algorithm to apply on each move in my mind. I won many times and lost as much.
How would one approach this game? How would one work in his mind to prune the possible moves and choose the "right" one in each step?
I see that most Othello CPUs more or less "think" the same at each move, how should I think on each move?

similar to older question:  https://boardgames.stackexchange.com/questions/9479/tactics-for-othello?rq=1
though, here are better answers

@Cohensius I am not sure if this is the right way to do it, but that one has already been marked as a duplicate of this one

I am not speaking as a highly expert player, but rather someone who always wins against people with little or no experience, and against overly simplistic computerized versions. So the approaches I've learned can get you from beginner to intermediate. I'll start with simple stuff first:
Corners are vital. Once you get a corner, it will never change color. More importantly, it is an anchor for getting many more pieces that will never change color. Once you do have a corner, if it's early enough in the game you can simply flip pieces to your color as close as possible to the corner, expanding gradually away from the corner and not doing any other types of moves. None of the pieces can be re-flipped, and eventually your opponent will have so few (or zero) moves that you can control the rest of the game in any way you like.
Key concept all beginners must grasp: All moves prior to the first corner being taken must be geared toward maximizing your chances of being the first to get a corner (or in rare instances, setting up the board to turn your opponent's first corner to your advantage). At the same time, you want to minimize the chances of your opponent gaining the first corner.
It's easier to think about avoiding bad moves than making good moves. The worst move that you can make in Othello is to play a piece diagonally adjacent to a corner. Even if the opponent can't immediately seize the corner after that move, it usually takes a turn or two to find a way to get the color flipped along that diagonal in a way that can't be re-flipped on your turn. The turn after that, your opponent gets the corner.
It can be thought of as less risky to go adjacent to a corner horizontally or vertically if you have control of that side. And it may be that for many turns thereafter it will not enable the opponent to get a corner. But unless forced to go adjacent to a corner like this, it's better to avoid it, for 2 reasons. One is that if the opponent does get that corner by other means, he'll then get the entire row you (thought) you controlled. A second, more subtle reason: If your opponent gets a corner on the other side of that row you control, their next move will be to get the corner you're adjacent to. Even if you do get that other corner, your opponent can use that other corner against you, like so (you are black, "controlling" the side with 5 blacks, then you get the corner coming in from another direction):
_ _ B B B B B _
B _ B B B B B _
B W B B B B B _

You can see that white can now take the other corner at any time, and irreversibly control the entire side except the corner on the left. This is what I meant earlier about turning a corner against someone. The only easy way to do this is if they have previously placed a piece adjacent to a corner along that same side.
Many people figure out everything I've written so far after 20-50 games. If you haven't already mastered all of the above, be sure to do so before trying to grasp the more complex and conceptual material to follow.
Concepts
There are several important concepts that drive Reversi strategy. First, to review the already mentioned concepts:

Avoid giving up a corner, and have that drive your early game
Avoiding bad moves is more important than making a good move
After getting your first corner, turn pieces to your color that are as close as possible to that corner.

A simple concept I did not yet mention:

The end game consists of simply counting the number of pieces you get vs the number of pieces your opponents get. This works fine for the last 2-4 moves of the game, but should rarely be a driving force behind moves in the earlier part of the game before the first corner is taken.

The most important game concept takes a long time to master:

Minimize the number of moves your opponent can make, while doing your best to insure that you maximize the number of moves that you can make.

When you are playing someone who has mastered the simpler parts of the game I described above, they will only make moves that allow you to get a corner if they are forced to. The only way you can force them is by limiting the number of moves they can make. You can do that only if you have many moves to make, some of which will not create further moves for your opponent.
I don't expect that most people will fully understand this last part of strategy I described without actually practicing. So I encourage anyone who likes this game to play a few games where your main goal is not to try to win, but to try to get used to making moves that have the result of reducing the number of your opponent's future moves while expanding your own set of moves. Once you get used to this, start trying to win again, using what you've learned to force your opponent to move adjacent to a corner, because that is the only remaining move (or one of a small set of equally bad moves).
One last note: The only player I ever struggled to win against had not played as much Othello as I had. But he was a good Go player. Apparently, Go players learn to think in a way that translates very well to Othello. Perhaps an experienced Go player can leave a comment explaining why a Go player learning Othello will grasp the game far faster than players without that background.

I used to play a lot of Othello casually online, and always followed this strategy.  I did well, but any time I was blown away by high rank players, I would end up with all 4 corners and little else

Cluster-borders (or border-lines) is a core concept to win, in my humble opinion, being a decent player:
1.
Counter-intuitively, in the beginning of the game, one of the tactics is to take as few pieces as possible. To elaborate on this: in mid game, it's key that you can force the opponent to make bad moves (e.g. giving corners to you). The way to limit the opponent's moves is that he has lots of pieces on the board, in 'border-lines', and you don't.
2.
Create border-lines for the opponent. Border-line means the contour of the cluster of pieces on the board. If a border line is all in the opponent's color, he cannot expand in that direction, and you are forcing him to place somewhere else.

In the picture, white has a border to the left and top. Black should avoid expanding left or upward as much as possible, to limit white options, forcing white to make bad moves towards the lower right.
3.
If you have the choice, take pieces inside of the piece-cluster and not on the border-lines. If you break an opponent-colored border-line, you lose advantage.

If you want all the strategy to be simplified into a single sentence, it would be:
Maximize mobility, aim for stable disks.
Disks are considered stable when they cannot be flipped again. For instance, corners, or filled up edges cannot be flipped.
Mobility is the number of different moves, in particular good moves, you have access to.
Disks that aren't stable holds no value except for a strategic one. Beginners often makes that mistake of trying to flip as many pieces as possible at each turn. But doing so goes against the principle of maximizing mobility, as the more pieces you flip in one turn, the less mobility you have in the future. The opponent can then use your low mobility to its advantage by forcing you to make poor moves due to how little choices you have left. Don't be that guy.
There's a ton left to learn about Othello strategy, such as traps, interior vs exterior disks, openings and the such, but they're all circumstantial, all subject to exceptions. Just remember those two principles and you'll be on the right track.


text:
Will Awakening let me tap all my lands and get them immediately untapped?
With the card Awakening, could I tap all lands immediately after my untap step and then have them untap upon entering my upkeep? I ask this because I'm trying to maximize Omnath, Locus of Mana as my commander.

What game are you talking about? I am assuming Magic, but there are other games with similar terminology.

With the reference to "Omnath", it's definitely Magic

You could use Awakening to tap your lands twice in one turn, but not exactly in the way you expect.
Starting with your untap step, play proceeds as follows:

Your untap step starts, and all of your permanents untap.
Your upkeep step starts, and Awakening's triggered ability goes on the stack. You gain priority. This is your first opportunity to do anything.
You can now tap your permanents to add mana to your mana pool.
Awakening's ability resolves, and all of your lands and creatures untap.


text:
What game has this weird 12 sided die with clouds, a bug, a pear and other stuff on it?
I found this unusual and hilarious die. I have no clue what it could be from. On the 12 faces I see these 4 particular shapes:

a lady bug or beetle
a vest or blouse
a creepy clown face
a partly eaten pear

and the rest of the 8 faces are clouds or bats(?)
Can anyone identify this game and help me figure out what this die is actually used for or what the figures really are supposed to represent?

Any individual strange die likely comes from a real game, but the number of games with strange dice is limited. Any individual strange die is unlikely to have been made by a prankster trying to mess with us, but the number of dice such a prankster could make and disseminate is virtually unlimited, and questions about those dice would be unanswerable. It follows that if enough of these questions stay unanswered, the correct answer to most of them probably becomes "you got pranked" :)

Dang it Google, I don't want to know how to dice a pear... No clue as of yet on what it's for, although they could be charades-like concepts. A food, an emotion, a piece of clothing, and... concepts? So they're thought bubbles?

Found it! Through sheer Google-fu, I discovered ThinkBlot!

Tom Vasel's review describes its use:

The game is very simple. Up to six players are given a sheet from a pad included with the game, along with a pencil. Then, the Thinkblot book is opened. It is a spiral bound book that transforms into an Easel with 75 different inkblot pictures, as well as a fold-out scoreboard. Each player places a peg into one of the colored paths on the scoreboard, representing his score.
Now, a special 12-sided die is rolled. Instead of numbers, there are little pictures or blots on each side of the die. Depending on what is rolled, the players write down things on their scoring sheet that they think they see in the inkblot currently showing. Whenever a little blot is rolled (eight of the twelve sides), players write down anything they see in the inkblot mess. When a little bug is rolled (one side), players should write down any creature they see in the picture. When a little face is rolled (one side), they are to write down people, parts of people, or actions taken by people. When a half eaten pear is rolled (one side), players should write down any food they see. And when a little shirt is rolled (one side), players are to write down any clothing or accessory they see.

I had serious doubts about them being clouds. They'd've probably made the die black and the spots white if that was what they wanted. Now it makes sense!


text:
Is putting multiple counters onto a target an atomic action?
Consider these two cards:
Fathom Mage

Whenever a +1/+1 counter is placed on Fathom Mage, you may draw a card.

Dragonscale Boon

Put two +1/+1 counters on target creature and untap it.

Would Fathom Mage's effect trigger once or twice?

The rulings for Fathom Mage indicate that a single effect placing multiple counters on it, causes its ability to trigger multiple times.

1/24/2013: If multiple +1/+1 counters are placed on Fathom Mage simultaneously, its last ability will trigger once for each of those counters.

As a result, Dragonscale Boon would cause the ability to happen twice, and you could draw up to two cards.

Hypothetically if Wizards wanted you to only draw one card when you cast Dragonscale Boon, they'd probably word Fathom Mage the way they did Hardened Scales.

Whenever one or more +1/+1 counters is placed on Fathom Mage, you may draw a card.

In this case, the ability only triggers once for each discrete event. Dragonscale Boon would only cause the ability to happen a single time.
If we gave Fathom Mage an ability like "RRR: put a +1/+1 counter on Fathom Mage", then you would be able to draw a card once for each time you activate the ability, regardless of how the triggered ability was worded. If you're adding more than one counter, you're activating the ability more than once, and each ability generates a brand new event.

The question has been reworked to specifically just ask about the combination of Fathom Mage and Hardened Scales.

@doppelgreener, thanks for the heads up. I'm thinking how I should revise my post.

If the ability reads as follows, it triggers for every counter.

Whenever a +1/+1 counter is placed on this object, you may draw a card.

If the ability reads as follows, it triggers once every time counters are placed on the object, even if more than one are placed.

Whenever +1/+1 counters are placed on this object, you may draw a card.

Fathom Mage's ability has the former form, so it triggers twice. This is codified by CR 603.2c.

603.2c An ability triggers only once each time its trigger event occurs. However, it can trigger repeatedly if one event contains multiple occurrences. [...]


text:
Can I always sacrifice a permanent whenever I want, without anything telling me to do so?
Can one sacrifice any permanent at any time for any reason, or is "permission" to sacrifice only granted by other cards?

I want to note that sacrifice isn't a special case. The rules say exactly what you can do and exactly when you can do it.

You can't spontaneously sacrifice a permanent. Even if you have a permanent with an ability of the form "whenever a creature dies" or "whenever a creature is sacrificed", you need to find some means of sacrificing it.

There's no rule forbidding it; there's simply no rule allowing it. CR 116 itemizes what actions you can perform. When you have priority[1], you can do the following[2]:

116.1a Cast a spell.
116.1b Activate an activated ability.
116.1c Perform certain Special Actions.

115.2a Play a land.
115.2b Turn a face-down creature face up.
115.2c Take an action an effect previously permitted you to take at a later time (usually to end a continuous effect or to stop a delayed triggered ability from triggering).
115.2d Take an action a static ability allows you to take to ignore the effect of that static ability for a duration.
115.2e Exile a card with Suspend.
115.2f Role the Planar Die.
115.2g Turn a face-down conspiracy card face up.

116.1d Activate a mana ability.

As you can see, sacrificing a Permanent is not an option (unless it's part of one of the above actions (e.g. The cost to activate an ability)).

There are other actions you can take (e.g. Drawing a card in your Draw Step), but they aren't actions you chose to do, so I won't bother listing them. They are itemized by CR 116.2.
Conditions may apply.

You can only sacrifice a permanent when instructed to do so by some ability. Even if you had another ability such as "when a creature is sacrificed...", you would need something else to let you sacrifice a creature.


text:
Can older cards that refer to a player/opponent ever be used on planeswalkers?
Many older cards refer to players or opponents, e.g. "deal 3 damage to target player". Can any of these be used on planeswalkers, beyond the fact that you can simply attack them with creatures?
For example:

Would my opponent discard a card if Hypnotic Specter damaged a planeswalker they control?

Would my opponent, the planeswalker, neither, or both amass poison counters from an unblocked Nafs Asp?

Can Lightning Bolt target a planeswalker?

Does Syphon Soul affect planeswalkers?

Can Oasis prevent damage to a Planeswalker?

Would Veteran Bodyguard be obligated to take damage being dealt to a planeswalker?

Can a planeswalker gain loyalty from Healing Salve?

Can Healing Salve prevent damage to a planeswalker?

@Jefromi I suppose I am seeking to understand the ways that pre- Planeswalker era cards can be effective in damaging/protecting Planeswalkers outside of an attack/defense context. Eg, is there any global Oracle text/definition that effectively updates older cards printed with "target creature or player" to instead be interpreted as "target creature, player, or Planeswalker", for example?

If there were, you'd see it on the cards you linked to. There's no secret Oracle text; what you see in Gatherer is it.

I think I pretty much understand what you're asking, so I've edited your question further, and for what it's worth, I would vote to reopen if it gets closed. Although it does perhaps show some lack of research effort, people do really commonly confuse "player" and "planeswalker", so I think it's very much a question worth having.

Planeswalkers are not players (or opponents), and they're never treated as players (or opponents). Don't think of them as players, and you'll be a lot less likely to get confused.
There's pretty much just a single rule that make them seem a little similar to players: you can choose to attack your opponent and/or planeswalkers they control.
Along with that, many cards will let you target a player or a planeswalker, e.g. Lava Axe says "target player or planeswalker", and Lightning Strike says "any target", which includes planeswalkers. (Note that thanks to some updates to the game, some older printings of cards may not make this clear, e.g. Lava Axe used to just say "target player", and Lightning Strike used to just say "target creature or player"; always check Gatherer for the current oracle text of a card if you need to be sure.)
But that's it. None of that actually treats planeswalkers as players; it just lets something happen to them that's similar to what can happen to your opponents.
There are no similar rules for any of the things you mentioned, so the direct answer to every one of your questions is no. There is definitely not a blanket revision from "target player" to "target player or planeswalker". (A ton of things that say "player" wouldn't even make sense for planeswalkers - sure, they can take damage, but they don't have hands, libraries, graveyards, or even life!)
To address your questions in a little more detail (some things do still work, just not directly):

Hypnotic Specter - no, attacking the planeswalker won't make your opponent discard. If you want your opponent to discard, attack them, not the planeswalker.
Nafs Asp (poison counters) - no, planeswalkers can't have poison counters; if it deals damage to one it'll remove loyalty as usual. If you want to give poison counters to your opponent, attack them, not the planeswalker.
Lightning Bolt - yes, it can target a planeswalker - it now says "any target". Again, note that older printings don't mention planeswalkers, but the current oracle text is updated.
Syphon Soul - no, it doesn't deal damage to planeswalkers, just players.
Veteran Bodyguard - no, it won't protect planeswalkers, since combat damage is dealt directly to the planeswalker and Veteran Bodyguard's effect never applies.
Healing Salve (gaining loyalty) - no. It can't target planeswalkers, and planeswalkers can't gain life (only players have life).
Healing Salve (preventing damage) - no, you can't target planeswalkers with it.

Beyond oracle updates ("target player" to "target player or planeswalker" and similar), the only other way that older cards are likely to literally target a planeswalker is if they say something like "target permanent" or "target nonland permanent"; planeswalkers are permanents too, so for example Desert Twister can target and destroy planeswalkers, despite being printed in 1993!

Note: I've entirely removed sections about the planeswalker redirection rule, which existed in the past but is no more. See the revision history if you're curious.

One final thing I would add is that planeswalkers, like everything else on the battlefield, are permanents and spells that target permanents (such as Vindicate) can also target planeswalkers.

This is a beautiful answer, and I appreciate it very much. @pixels, your addendum is much-appreciated as well. I do believe I understand now. Thank you!

@pixels Edited in, thanks. It didn't occur to me because I was so focused on the idea of player != planeswalker!

This rule will be changing in MTG.  The damage redirection rule will be removed and spells that target players will be amended to target players and plainswalkers.

@QthePlatypus Do you have a more recent reference than Mark Rosewater's post from October 7? He just said "soon" at that point, so it's hard to add much of anything solid to the answer.

Now incorrect as of March, 2018 (rules change). In short, planeswalkers can how directly be targeted by anything that hits "any target", or "any opponent" and there's a lot of errata out on existing cards.
See: https://magic.wizards.com/en/articles/archive/news/dominaria-frame-template-and-rules-changes-2018-03-21

The Oracle text for Healing salve now says "Prevent the next 3 damage that would be dealt to any target this turn." so it should be able to prevent damage to a planeswalker

A Planeswalker is never a player. Spells that target a player can't target a planeswalker.
However, noncombat damage can be redirected to a planeswalker (damage only, not lifeloss), but it doesn't affect the player anymore when you do that.
So cards like Hypnotic Specter won't cause the opponent to discard a card if damage is redirected, since the damage is redirected to the planeswalker, and the player takes no damage.

It's only noncombat damage that can be redirected to a planeswalker. I think you meant that Hypnotic Specter won't do its thing if you attack the planeswalker - the combat damage isn't redirected, it's just dealt directly to the planeswalker. (And Hypnotic Specter makes them discard, not draw.)

This is no longer accurate as redirection has been removed in a recent rules update. All old cards that made use of this redirection have had their oracle text updated IE lightning bolt is now "Lightning Bolt deals 3 damage to any target." instead of "Lightning Bolt deals 3 damage to target creature or player."

Planeswalkers are never treated as opponents.
As to your specific questions: no, no, no, no, no, no, and no.

this is wanting of explanation. (some of these responses are factually incorrect or at least desire explanation, e.g. lightning bolt can't target a planeswalker but it can damage one.)


text:
Does the Strive mechanic give the opportunity to cast the spell multiple times, or just have multiple targets?
I'm wondering if the strive mechanic counts as one spell that can be cast multiple times by paying the extra cost, or is it just one spell that can affect multiple targets if you pay the mana?
I'm wondering if the prowess ability of the Jeskai would stack with one spell cast with the stride mechanic and subsequently paying the extra mana. Would that trigger prowess a second, or third time?

It's just one spell with (potentially) multiple targets. It doesn't count as being cast multiple times, and it will only trigger Prowess once.
Taking Aerial Formation for an example, the text says:

Strive — Aerial Formation costs {2}{U} more to cast for each target beyond the first.

Any number of target creatures each get +1/+1 and gain flying until end of turn.

This is known as an additional cost. As its name might suggest, it just increases the mana cost of the spell—it won't count as casting it more than once. Incidentally, it's handled by competitive rule 601.2b, the same rule that handles the {X} in mana costs. It's the same kind of thing: another flexible mechanism where you pay more to improve the spell.
Suppose you want to target three creatures: you announce you intend to pay that cost twice, so you add 4UU to the mana cost of the spell (normally just U), making the spell cost 4UUU total. Then you pick your three targets, pay the cost, and put the spell on the stack. Now the spell's cast, and Prowess is triggered once.
Other abilities which add additional costs to spells are Kicker (Citanul Woodreaders) and Buyback (Capsize). Then there's Multikicker (Bloodhusk Ritualist) which, like Strive, can be paid any number of times.

A minor note: Multikicker counts as a type of kicker. That's why it's not mentioned separately in 601.2b.

The order of events for casting the spell is a little funny to me, considering rule 601.2.

Casting spells with Strive just increases the possible number of their targets, it doesn't trigger Prowess multiple times.
There are abilities that copy spells like Storm and Replicate and also spells that copy other spells(for example Reverberate) but they won't trigger Prowess either since copies of the spells created with them are not casted.
Although copies of noncreature cards can be cast and trigger prowess. Example - Elite Arcanist


text:
Does Republic of Rome usually generate one or more wars per turn, leading to a loss even when cooperating?
I have played Republic of Rome several (4?) times with a group (usually 4-5 players) without studying the rules myself. We have always started in the Early Republic period, and even when we try to cooperate just to survive the period, we have always lost, generally to an onslaught of wars, often more than one per turn. We always end up facing at least one Punic War and usually four or more in total, and get overwhelmed by one thing or another as a result. The others have played it many more times than I have with them, and they say they have NEVER made it out of the Republic period, due to losing one way or another.
Are we playing the game wrong? I think the main cause is overwhelming random events, specifically accumulating wars. Each game turn, each player draws at least one random event card, and this can and in our games has often resulted in one or more new war about every turn. Does the game have a rule we are missing that at least limits the number of random wars entering play to one per turn at most?
Also, from a historical perspective, it seems like the time scale must be abstract and a bit off. It feels like each game turn is a year, but then obviously there were never new wars coming up every year historically.

There is cooperating, and there is cooperating; the latter is needed in the Early Republic to overcome Hannibal and Philip. Many years ago I played this game every Friday night for several months - we only once, early on, failed to win the Punic and Macedonian Wars when Hannibal, Hamilcar, Second Punic and Both Macedonian Wars and Philip all arrived first turn. Anything less we could handle with sufficient sacrifice.

Thanks. That answers that multiple wars are supposed to be able to happen, and can be survived. We were just trying to survive in the last few games, and it seemed possible but we kept getting more problems and failed each time.

You really do need to read the rules, more thoroughly than it sounds as if the rest of the group has done. If you do, you will find that RoR is not a common-or-garden multiplayer game where an ally is somebody you have no reason to attack at present; it is designed so that the players all have to genuinely co-operate to keep the state going, and the winner is the one who can use each successive crisis to best advantage. The designer's notes say "I designed it for those who find Diplomacy too tame", and you need to be a born politician to find the game easy. But the notes also include a page or two of suggestions, and here are one or two of my own.

The object of the game is not to preserve the Republic; it is to have yourself declared Emperor (or some near-equivalent). One of my favourite winning conditions is being in rebellion when the state goes bankrupt; presumably the Ancient World Bank then puts you in charge of rebuilding, Monti-style.
The Early Republic scenario is well-known to be the hardest to survive; if you don't like it, try the Middle or Late Republic scenarios, or even the optional one where you shuffle all the cards together and use the top fifty or whatever. But bear in mind the reason (mentioned in the rulebook) that not every year is represented by a turn: a year when nothing happens is a year when nobody has a chance to affect the game. If you are not versed in the subtle politics going on around you, a game without wars is going to seem quite dull - until someone else suddenly wins.
There are precisely six random events each turn, and a lot of possible wars. When you include the enemy leaders then yes, you are going to have to do a lot of fighting; at least one war a turn. You can't afford to say "I'm not voting to give that general a chance to shine", or "I'm not contributing to the treasury unless everybody does"; rebuild the army, and send it out to fight.
Setting the terms of the debate is a huge advantage: if the HRAO (think President) has done his job, you have an unpalatable choice between everybody losing and making someone else's victory easier. But of course you may be HRAO yourself next turn...
You need to think quite seriously whether you would rather have somebody else win or everybody lose (see this question). Of course, if you are winning, you need to consider that the other players are also thinking this, and won't give you an easy ride. A lot of Early Republic games end in one climactic battle; if the army loses, the state collapses, and if it wins, the general has enough prestige to win the game. But he might be killed while winning the victory, which would give others a chance, so it's worth voting to send him out; now, how many legions do we send to maximise the odds? Unless you think this way every turn, you won't be a good RoR player; be consoled by the fact that you are probably a nicer person for it.

We did at least get from the beginning that it's a tangled political game with preventing others' wins a main element, with the war hero dilemma a common problem. I was hoping to win as the least distrusted. The first time I played, there were plenty of politics. Scipio had to wait until we were desperate enough to send him to war, then someone assassinated him to keep him getting too popular, leading to a series of retribution assassinations, which was followed by a plague and ill omens, wiping out all of my and just about all of our senators. Game over, VIRUS!

The main thing I wasn't aware of that you mentioned, is the ability to win by being in rebellion when the state goes bankrupt... but I think it's unrest (mainly from unpersecuted wars) that ended all our games, not bankruptcy.


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Why can an ability resolve even if I exiled the creature it came from?
I just started learning magic a week ago and I've been playing duels of the planeswalkers 2014 to kind of get a hang of things.
I'm confused with something that has happened twice now. I'm playing against a campaign deck with a Goblin Fireslinger which has an activated ability that says:

{T}: Goblin Fireslinger deals 1 damage to target player.

So this gets cast while I have the instant Path to Exile in my hand, which "Exile(s) target creature." So I cast that.
Now it is my understanding with the way the stack works that once the GF uses its ability and then I follow it up with the Exile, the exile is resolved first so the GF should be exiled before it can resolve. And that's what the game does, but it still resolves the GF's ability while that card is exiled and deals me one damage.
I tried looking for why this could have happened, but I haven't been able to find an answer myself. I can't find anything that says an exiled spell still casts... I'm just confused about the way this works.

If you're looking for a more thematic explanation, in addition to the (correct) answers given below, think of activating the Goblin's ability as throwing a grenade at the target. Now that the grenade has been thrown, getting rid of the goblin isn't going to help, even if you do it before the grenade explodes.

possible duplicate of Does an activated ability resolve if the card with the ability is returned to its owner's hand? and also Does a heroic trigger still resolve if the heroic creature is gone?. Both are asking if removing the source of the trigger removes the trigger itself.

Removing the source of an effect does not remove the effect.  Simple rule to live by.

Your understanding of how the stack works is correct: your path will resolve and exile the fireslinger before its ability resolves. What you're missing is rule 112.7a, which says that the fireslinger's activated ability exists independently of the fireslinger. Once you put it on the stack, the 1 damage is its own object and exists even if the fireslinger itself leaves the battlefield:

112.7a Once activated or triggered, an ability exists on the stack independently of its source. Destruction or removal of the source after that time won't affect the ability. Note that some abilities cause a source to do something (for example, "Prodigal Pyromancer deals 1 damage to target creature or player") rather than the ability doing anything directly. In these cases, any activated or triggered ability that references information about the source because the effect needs to be divided checks that information when the ability is put onto the stack. Otherwise, it will check that information when it resolves. In both instances, if the source is no longer in the zone it's expected to be in at that time, its last known information is used. The source can still perform the action even though it no longer exists.

If you want to actually counter the ability, there are very few ways to do so. Less than 20 cards in all of magic can counter activated abilities.

Isn't there just one or two cards that directly counter abilities? Granted, giving the target Hexproof or Protection from Red would counter the ability. (In both case, Last Known Information will supply the Goblin's color and its controller.)

@Ikegami stifle, squelch and voidslime all counter abilities, and there's at least 11 cards that mention countering activated abilities

@ikegami, by my count: eight cards that can counter any activated ability, one card that can counter most activated abilities (creature/artifact/enchantment/land source), and four cards that can counter activated abilities of artifacts.

That has already been pointed out. Anyway, the point of my post was to introduce the reader to the concept of invalid targets on resolution and LKI.

This is part of your confusion:

I tried looking for why this could have happened, but I haven't been able to find an answer myself. I can't find anything that says an exiled spell still casts... I'm just confused about the way this works.

It isn't a matter of "an exiled spell still casts" here.
A spell is a card on the stack: an instant, sorcery, creature, etc. When Goblin Fireslinger was being cast, just before it entered the battlefield, it was a spell. When Path to Exile was being cast, before it resolved, it was a spell. Those are the only two spells involved in this scenario.
Goblin Fireslinger doesn't create a spell. As you pointed out, it has an activated ability. When you activate it, that puts an activated ability on the stack. (That's important: it means you can stop it with Stifle, but not with Cancel.) If you're imagining the Goblin itself, which you exiled, was on the stack in some capacity, that's not the case.
So, the Goblin got exiled just fine and won't be doing anything else, but its ability is now its own thing still on the stack waiting to resolve.
And that ability exists independently of it. Check the Basic Rules, page 14:

If you activate an ability but then the permanent the ability came from leaves the battlefield, the ability will still resolve.

That's why its ability can get resolved even whilst the Goblin isn't still there.
If you want to learn more about how spells and abilities work, I suggest you read those pages in the Basic Rules book, and possibly for further clarification read this answer that helped me a lot when I was new. In fact, if you haven't read the Basic Rules yet, I suggest you do! I never knew they existed until a while after I started.

When you activate an ability (the damage ability, for example), it exists on the stack as its own object independent from the object it was activated from (Goblin Fireslinger, for example). So even if you exile the Goblin Fireslinger, the ability is still on the stack and it still resolves.

As other people have already pointed out, Goblin Fireslinger's ability still resolves because the ability exists independently of the creature itself. So something would have to happen to the ability rather than the creature.
To expand a bit on what everyone has said about countering abilities - although there are very few cards that will directly counter an ability, what you can often do much more easily is to make its target(s) invalid. Spells or abilities that don't have any legal targets when they try to resolve are automagically countered (rule 608.2b).
E.g. you could cast Gilded Light while Goblin Fireslinger's ability was on the stack, and the ability would be countered. There aren't many ways to make yourself an invalid target, but there are lots of ways to do this with creatures and other permanents.


text:
7 wonders: copying science
I'm playing 7 Wonders with the Cities and Leaders expansions.

If your neighbours has less science buildings than you have mask, then I assume you cannot use them all. You can only copy the symbol of 1 building once?
If one of your neighbours has a leader which carries a symbol, can you copy this?7

The rules state:

At the end of the game, each mask allows the controlling player to copy the scientific symbol of a green card present in one of the two neighboring cities.
If a player possesses multiple [mask] symbols, he or she can only copy a given card once, and must thus copy as many different cards as they have [mask] symbols.
A player can copy two identical cards (if they have enough masks) if both neighboring cities have a copy (copy a Workshop card in the left city and a second Workshop card in the right city).

Example: At the end of the game, Alex has 2 cards with the [mask] symbol. The player to his left only has one green card, with the compass symbol. The player to his right has played no green cards. Alex’s first [mask] therefore counts as a [compass] symbol, but his second [mask] is useless as there are no other symbols to copy. If the player to the left of Alex had had 2 green cards with a [compass] symbol each, Alex’s 2 masks could’ve counted as [compass].
So the wording is pretty clear. For each mask symbol you control, you may copy the symbol of a single green card owned by either adjacent player. Hence,

You may not copy the same building, even if you have more masks than buildings.
You may not copy the symbol on a leader, since they are not a building / green card.


text:
7 wonders: builder's chambers
If I build the Builder's Chambers at the same time as someone builds his first wonder stage, should he be charged?

(I assume you mean Builders’ Union, where other players have to pay 1 coin to the bank for each Wonder stage they built.)
Yes, players have to pay also for stages built in the same turn.
From the Cities rules about Debts (page 4):

Important : monetary losses are always resolved at the end of a turn, after players have played their cards, possibly having paid for trade and/or obtained money...

In the rules it says Union. On the card, it says Chambers.

@Lost1: Ah okay, didn’t know that (I’m playing with German cards).


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What effect does Coat of Arms have on face-down creatures?
I was playing a Sliver deck vs a co-worker today, and he played an illusion deck with Ixidron. I was having a hard time grasping how Coat of Arms would work with Ixidron turning everything face down.
Ixidron basically says all face-down cards are creatures. Is creature a type that Coat of Arms would be pairing with and make everything huge, or would coat of arms essentially do nothing to all of those face down cards?

From that same page (emphasis mine):

Creatures turned face down by Ixidron are 2/2 creatures with no text, no name, no subtypes, no expansion symbol, and no mana cost.

"Creature type" is a shorthand for a creature-specific subtype (205.3m in the Comprehensive Rules). Face-down creatures have no creature type, so Coat of Arms does not affect them.

So, you are essentially saying that Coat of Arms specifically effects only subtypes and since it only gets a base type of creature then it has no subtype and therefore coat of arms doesn't work on it?

@dphil: Correct. Creature types are a subtype.

@dphil, "Creature type" is short for "creature subtype", of which Sliver is an example.

The shorthand is codified in comprehensive rule 205.3m Creatures and tribals share their lists of subtypes; these subtypes are called creature types

@ChadMiller It might be good to reference that shortcut, and state in your answer that 'creature type' refers to certain subtypes.

You guys are allowed to edit, you know. But will do. ;)


text:
Do multiple Gray Merchant of Asphodels trigger each others' enters-the-battlefield effects?
If there is a Gray Merchant of Asphodel on the battlefield and a second Gray Merchant of Asphodel enters, do both cards trigger and opponent loses x life where x is devotion times 2, or does just the one card entering the battlefield trigger?

No, only the one entering the battlefield triggers.
Any time you see a card use its own name in its rules text, that means it is referring to the card that it is printed on; not other cards with the same name.

201.4. Text that refers to the object it's on by name means just that particular object and not any other objects with that name, regardless of any name changes caused by game effects.

Because "When Gray Merchant of Asphodel enters the battlefield," is far more readable than "When the object on which this ability resides enters the battlefield,"

@ikegami Do you know why they didn't just use "When this enters the battlefield"?

I was going to say "because abilities don't enter the battlefield", but some keyword abilities use "When this permanent is ...".


text:
Munchkin: card attributes in the event of helping another player
Assume that a player turns up the Ogre Achiever upon kicking down the door, and cannot kill it alone.
Given that the card's description (excluding 'Bad Stuff') is:

+5 against anyone who doesn't have a Class and a Faction.

(bold emphasis mine)
If the original player who looted the room and the person helping both do not have a class and a faction, would the resulting monster have +10 against the team of 2 players?
If so or if not, a specification from the rulebook would be appreciated! I have had no luck in finding anything in the original game's rulebook nor the expansion (Pathfinder).

I don't know where the rule is stated explicitly, so I won't post it as an answer. But I believe such modifiers can only be activated once. As the drawing player already triggered that modifier, the helping player cannot trigger it again.

I haven't been able to find a specific rule in either the rule book or FAQ but the following post from the Steve Jackson Games forum. According to them, the card must explicitly state that the effect stacks. So in your case, the maximum would be +5 to the monsters level.

In my examples, x will always be 5, y will always be 2. A will be
  Dwarf and B will be Elf. The Dwarf/Anything or Elf/Anything means
  Anything except human. The reason behind this is because of the
  Half-breed card that allows you to ignore disadvantages of the single
  race you have, as long as you have Half-breed too.
1: +x against A & B = +x if A and/or B.
Monster Card says: +5 against Dwarf & Elf
It means that the monster gets a +5 if you're a Dwarf, Dwarf/Anything,
  Dwarf/Elf, Elf/Anything, Elf.
2: +x against A & B and it stacks = +x if only A or only B, +2x if A & B.
Monster Card says: +5 against Dwarf & Elf, and card specifies that it
  stacks.
It means that the monster gets a +5 if you're a Dwarf OR an Elf. If
  you're a Dwarf AND an Elf, the monster get +10 in this case.
  Dwarf/Anything minus Elf and Elf/Anything minus Dwarf only get +5.
Important note; a Monster getting a bonus against multiple races
  usually only get the bonus once. Same for multiple classes, or other
  such things, since they're the same source; Bonus vs Race, or vs
  Class, or vs whatever. HOWEVER, a combination of those, a Bonus vs
  Race AND a Bonus vs Class will always stack, since it's a different
  source. Only the monster cards that SPECIFY that their bonus stack for
  2 different Races, Classes or Whatever, will have it stack. An example
  of such cards would be #3.
3 +x against A, +y against B = +x if only A, +y if only B, +(x+y) if A & B.
Monster Card says: +5 against Dwarf, +2 against Elf. +7 if both.
This one is fairly simple. It means that if you're a Dwarf or
  Dwarf/Anything, minus Elf, the monster gets a bonus of +5. If you're
  an Elf or Elf/Anything, minus Dwarf, the monster gets a bonus of +2.
  If you're Dwarf/Elf, the +5 and +2 stack, and create a +7 bonus for
  the monster, hence the "if both".
Negatives can appear instead of those positive Bonuses. Some might
  even have both, in which case one would be added and the other would
  be substracted. In my examples, it would be something like +5 against
  Dwarf, -2 Against Elf. In this case, it doesn't have to specify "if
  both" because, while they're from the same source (Race), one's a
  Disadvantage (the +5 against Dwarf) and the other's an Advantage (the
  -2 against Elf).

The rules (in bold) themselves supposedly come from Steve Jackson (although I can't confirm that), the further explanations are from a forum member.

I'll vote up for you explanations of other scenarios that are specific for particular cases where the language is clear - but in this particular situation I'm questioning the word anyone, which could apply to just the original door-kicker or the entire team (individually), which affects the result of combat.


text:
What is this game with 16 pegs and 36 spools to fit on them?
This board has 36 spools that fit on 16 pegs or sticks.
It looks like it might be 3D checkers or something like that.
Interested in the name and how to play.

Someone took a lot of time making this really nice board game and I would like to use it properly.

Hi, and welcome to the site! I've removed the signature from the end of your question, since we tend to do away with salutations and signatures here - your question is already signed with your user card beneath it after all.

This looks a version of a game I used to own called Score Four. It is essentially the classic Connect 4 game, but in three dimensions instead of two.
It plays exactly as you would imagine

players take turns adding pieces of their color onto pegs
the first player to create a line of 4 in any direction (vertical, horizontal, diagonal) wins

It is considerably more interesting than Connect 4
http://boardgamegeek.com/boardgame/3656/score-four

I had the chance to play this game before: it's a 3D version of the classic game Connect 4 and as far as I know the same rules apply.
Although it looks very cool, in my humble opinion there are too many possibilities and it's far less fun than the 2D version. I'm not sure if it's patented and/or if there are "official" rules.


text:
Would stealing control of my opponent's commander with Control Magic and killing it let me maintain control of it?
If I played Control Magic and enchanted Marath, Will of the Wild, then took off the 3 counters, would Marath return to my opponent's command zone or would I retain control and have the option of casting him for his mana cost?

No, you won't retain control. Your enchantment will fall off and go to your graveyard, and Marath will go to your opponent's graveyard or command zone.
The primary reason is that when a creature changes zones, this rule kicks in:

400.7. An object that moves from one zone to another becomes a new object with no memory of, or relation to, its previous existence.

Also, whenever a creature dies, it moves to its owner's graveyard - not its controller's. You don't become Marath's owner, just its controller temporarily. (There are lots of different rules covering the situations a creature might  die, but they all handle it the exact same way.)
When Marath dies, he (she? I don't know) is going to move to his owner's graveyard like any other creature. If Marath is your opponent's commander, your opponent has the option to instead move him to the command zone.

903.11. If a commander would be put into its owner’s graveyard from anywhere, that player may put it into the command zone instead.

Either way, Marath changes zones. From the perspective of your Control Magic enchantment, the creature it enchanted has vanished completely, and so the enchantment goes to your graveyard. It doesn't move with Marath, just like how cards don't stay enchanted when they move to your graveyard. Elsewhere, in another zone, a brand new object called Marath, Will of the Wild appears, with no relation to the creature the enchantment once enchanted.
Your opponent regains total control of Marath, and can cast him from the command zone as usual (if your opponent chose to move him there, instead of to their own graveyard).
Even if you manage to take "permanent" control of Marath (e.g. with Perplexing Chimera), you still don't own him, and he'll return to your opponent's graveyard or command zone when he dies. Control of Marath is returned to your opponent completely thanks to 400.7 and business as usual resumes.


text:
Will Repercussion deal damage to a controller beyond a creature's toughness?
Repercussion's text reads as follows:

Whenever a creature is dealt damage, Repercussion deals that much damage to that creature's controller.

So: if, for example, a 1/1 creature is dealt 10 damage with Repercussion in play, does its controller take 10 damage or 1?

It's as you said: The creature was dealt 10 damage, and Repercussion deals that much damage.

Sure. It just seemed too broken to not be banned/restricted.

@intuited nah, it's not a particularly strong card. Dealing massive amounts of damage to a creature isn't that much easier than doing the same to a player. Sure, it can make a cool combination with something like Earthquake, but that's a difficult enough interaction to exploit that Repercussion is nowhere near strong enough to be banned or restricted.

The controller takes 10 damage. A creature's toughness does not limit the damage it can take. Toughness just indicates how much damage is enough to destroy it.


text:
How many kings is it possible to have on the board at once?
Keeping in mind the force capture rule, how many kings is possible to have (of one colour) on the board at once in Checkers? What is the sequence leading up to this?

Are the answers not "2" and "any sequence legally possible in chess"?

@hexparrot: Chequers, not chess.

Haha teach me to be so reckless! Was reading chess puzzles for an hour and then saw this. Embarrassing oversight, my apologies!

I guess it also depends on what rules of Checkers you are playing. There are many variations with 8x8 boards, 10x10 boards, flying kings, men (not) being able to capture backwards. See http://en.wikipedia.org/wiki/Draughts . What variation are you talking about?

@Ivo 8x8 board, men, king promotion, king is just a man but can move backwards.

This question appears to be off-topic because it is about game state trivia and not actually playing the game.

@ColinD I don't see why that makes it off topic. We have rather a lot of questions about games that are not also about playing the game.

@doppelgreener its all about 'usefulness'. I do not think an answer to this question will ever impact a real game of checkers.

@Colin This is Board and Card Games, I had a question about a board game, I didn't see another appropriate site on the network, I researched it and couldn't find it, can someone please answer?

@warspyking it could just be that nobody's answered because nobody who's yet seen the question knows the answer

For American checkers on an 8x8 board, it is possible to get 24 kings on the board from the initial position. Here is a Java applet with a proof game of 211 moves.
For International draughts on a 10x10 board, it is possible to get 40 kings on the board from the initial position. Here is a Java applet with a proof game of 389 moves.

If your opponent is remarkably cooperative, you could, theoretically, get 12 kings on the board for your color.
Your opponent needs to open paths for you to get their back row in such a manner that you either do not get captured or can capture him on the way in.
I've had as many 8 in a game a couple times playing against a very not good opponent.

What's the move sequence for 12 kings then? Please edit that in your answer so I can mark it as accepted.

@warspyking - not sure off the top of my head, and no checker board handy to play both sides to get the optimal turnout