20 cards for 40 dollars. Hmmmmmmmmmmmm. Seems like it's a lot more lucrative to reprint cards and steal value out of the secondary market, than it is to design good sets to sell new booster packs.
It can't be both. Either it's a spell ability, or it's not.
112.3a Spell abilities are abilities that are followed as instructions while an instant or sorcery spell is resolving. Any text on an instant or sorcery spell is a spell ability unless it’s an activated ability, a triggered ability, or a static ability that fits the criteria described in rule 112.6.
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112.6b An ability that states which zones it functions in functions only from those zones.
If the ability said, "As long as this card is encoded on A creature, ...," then I'd definitely classify it as an exile-functioning (non-spell) ability. But it says "that creature", which makes it a little less clear to me.
You can't do that. Have you read the Oracle text? You need to pay at LEAST the creature's mana cost in order to cast it with the Mask. Once you do, there's no cost associated with it turning face up.
“Cipher” means “If this spell is represented by a card, you may exile this card encoded on a creature you control” and “As long as this card is encoded on that creature, that creature has ‘Whenever this creature deals combat damage to a player, you may copy the encoded card and you may cast the copy without paying its mana cost.’”
Re. the part of cipher that grants the creature the triggered ability: Is it an instruction that sets up an effect during the resolution of the spell, or is it a traditional static ability that functions while the card is exiled? I could kinda see it being read either way...
Yep. No reason for you not to be able to block with them.
To clarify a bit: You say that you played the Coatl to block one of them, but what actually happened was (1) you played the Coatl before blockers were declared, and then (2) you blocked with the Coatl.
No, for the same reason you don't have to T the Manipulator again: Copying a spell or ability on the stack doesn't involve paying any of the costs again.
Populating a Splinter Twin token will not cause the new token to be exiled at end of turn. The wording is the exact same as Kiki that being a delayed trigger. Heat Shimmer does work the way you said though.
Compare the delayed triggers set up by Séance and Kiki-Jiki (which won't affect populate copies) with written-on-the-token triggers like Heat Shimmer and Splinter Twin (which will appear on populate copies).
However many total cards are in your opponents' graveyards.
Quote from CompRules »
208.2a The card may have a characteristic-defining ability that sets its power and/or toughness according to some stated condition. (See rule 604.3.) Such an ability is worded “[This creature’s] [power or toughness] is equal to . . .” or “[This creature’s] power and toughness are each equal to . . .” This ability functions everywhere, even outside the game. If the ability needs to use a number that can’t be determined, including inside a calculation, use 0 instead of that number.
1- If I bring a legendary creature by using Sneak Attack, can I bring it back in my hand using Karakas after it dealt damage and before I have to sacrifice it?
Sure, why wouldn't you?
2- If I use Past in Flames to cast say Banefire, is X automatically zero or can I pay whatever amount of mana to deal damage?
From Gatherer:
If you cast an instant or sorcery with {X} in its mana cost this way, you still choose the value of X as part of casting the spell.
I have a semi related question which is hopefully close enough to sidetrack a bit here. Would that apply to something like Basilisk Collar too? Or would turn strip it's LL/DT because it says it gives the ability to the creature?
When figuring out continuous effect interactions, effects that add or remove abilities are applied in the same layer. And the two effects are independent, so you just use timestamp order. So--assuming that the Collar was already in play--Turn will strip away the deathtouch/lifelink. (unless the Collar's timestamp gets refreshed by moving it off/on the creature)
Characteristic-defining abilities, like Tarmogoyf's, are an exception to that, but the Boar's ability doesn't fall into that category.
To clarify a bit: You say that you played the Coatl to block one of them, but what actually happened was (1) you played the Coatl before blockers were declared, and then (2) you blocked with the Coatl.