I use Vesuvan Shapeshifter to copy (via morph) a face-up Bane of the Living . The board-wipe ability triggers, with an undefined X. Intuitively I would guess X to default to zero, but I cannot find a rule in 107.3 that supports that conclusion:
107.3. Many objects use the letter X as a placeholder for a number that needs to be determined. Some objects have abilities that define the value of X; the rest let their controller choose the value of X.
107.3a. If a spell or activated ability has a mana cost, alternative cost, additional cost, and/or activation cost with an {X}, [-X], or X in it, and the value of X isn't defined by the text of that spell or ability, the controller of that spell or ability chooses and announces the value of X as part of casting the spell or activating the ability. (See rule 601, "Casting Spells.") While a spell is on the stack, any X in its mana cost equals the announced value. While an activated ability is on the stack, any X in its activation cost equals the announced value.
107.3b. If a player is casting a spell that has an {X} in its mana cost, the value of X isn't defined by the text of that spell, and an effect lets that player cast that spell while paying neither its mana cost nor an alternative cost that includes X, then the only legal choice for X is 0. This doesn't apply to effects that only reduce a cost, even if they reduce it to zero. See rule 601, "Casting Spells."
107.3c. If a spell or activated ability has an {X}, [-X], or X in its cost and/or its text, and the value of X is defined by the text of that spell or ability, then that's the value of X while that spell or ability is on the stack. The controller of that spell or ability doesn't get to choose the value. Note that the value of X may change while that spell or ability is on the stack.
107.3d. If a cost associated with a special action, such as a suspend cost or a morph cost, has an {X} or an X in it, the value of X is chosen by the player taking the special action as he or she pays that cost.
107.3e. Sometimes X appears in the text of a spell or ability but not in a mana cost, alternative cost, additional cost, or activation cost. If the value of X isn't defined, the controller of the spell or ability chooses the value of X at the appropriate time (either as it's put on the stack or as it resolves).
107.3f. If a card in any zone other than the stack has an {X} in its mana cost, the value of {X} is treated as 0, even if the value of X is defined somewhere within its text.
107.3g. All instances of X on an object have the same value at any given time.
107.3h. Some objects use the letter Y in addition to the letter X. Y follows the same rules as X.
(a-c) do not apply because this is neither a spell or activated ability. (It is a triggered ability with an undefined X) (d) applies to Bane of the Living, but not to Vesuvan Shapeshifter; there was no X in the cost of the special action to turn VS face-up. (e) looks like it applies but implies that I would be able to choose any value of X that I wanted upon resolution (as funny as this would be, it's a bit absurd) (f-h) are irrelevant.
Yes. You're overlooking the fact that you paid Vesuvan Shapeshifter 's morph cost to flip it over, not Bane of the Living 's. The ability still triggers, but it looks for what you paid for X. You didn't pay for X. Therefore, X is 0.
I don't see the rules support for that conclusion. Frankly, now that I look at the rules for X costs, I don't see how Bane of the Living is even supposed to work, given that Morph's not an activated ability. If you turned a Bane of the Living face-up with X=5, turned it face-down again , then broke it open , wouldn't the value of X still be 5 since a value was chosen and it's still the same object?
Edit: To be clear, since isn't an activation cost, I don't see the rules support that the triggered ability uses the value for X chosen when the morph cost was paid.
107.2. If anything needs to use a number that can’t be determined, either as a result or in a calculation, it uses 0 instead.
If this is the rule I'm supposed to abide by in this situation, can you give me an example for when I would use 107.3e? Otherwise, I don't understand how I'm supposed to know the difference between "undefined and can be determined" and "undefined but can't be determined".
If you turned a Bane of the Living face-up with X=5, turned it face-down again , then broke it open , wouldn't the value of X still be 5 since a value was chosen and it's still the same object?
I...would actually like to know the answer to this as well. (For the sake of argument, assume that Bane has a bunch of +1/+1 counters on it so that it never dies during these processes)
107.2. If anything needs to use a number that can’t be determined, either as a result or in a calculation, it uses 0 instead.
If this is the rule I'm supposed to abide by in this situation, can you give me an example for when I would use 107.3e? Otherwise, I don't understand how I'm supposed to know the difference between "undefined and can be determined" and "undefined but can't be determined".
Example, where X is defined: Accelerated Mutation If there is no permanent under your control AM can't determine X and treats it as 0 as per 107.2
If you turned a Bane of the Living face-up with X=5, turned it face-down again , then broke it open , wouldn't the value of X still be 5 since a value was chosen and it's still the same object?
I...would actually like to know the answer to this as well. (For the sake of argument, assume that Bane has a bunch of +1/+1 counters on it so that it never dies during these processes)
The thing you choose the value of X for is the cost to end the morph effect. This morph effect. Not another, that the permanent might be under at a later time.
I've been searching the Comp Rules for a while and have to agree, that there seems to be nothing to support how Bane of the Living is supposed to work.
I'm a Rules Advisor now
"Simple questions" usually need rather complex answers, while complex questions often come down to no more than a simple "yes" or "no".
107.3d If a cost associated with a special action, such as a suspend cost or a morph cost, has an {X} or an X in it, the value of X is chosen by the player taking the special action as he or she pays that cost.
707.11. If a face-down permanent would have an “As [this permanent] is turned face up . . .” ability after it’s turned face up, that ability is applied while that permanent is being turned face up, not afterward.
Am I missing something?
«Dystocracy : A system of government in which corrupt leadership colludes with dishonest bankers and greedy elites in order to ensure that productive members of society –people who actually do useful work- bear the greatest share of taxes while gaining the least benefit possible.»
The thing you choose the value of X for is the cost to end the morph effect. This morph effect. Not another, that the permanent might be under at a later time.
Confirmed:
702.35d If you have priority, you may turn a face-down permanent you control face up. (...) The morph effect on it ends...
«Dystocracy : A system of government in which corrupt leadership colludes with dishonest bankers and greedy elites in order to ensure that productive members of society –people who actually do useful work- bear the greatest share of taxes while gaining the least benefit possible.»
