See rule 410, “Handling Triggered Abilities.” In other cases, X is defined by the text of a spell or ability. If X isn’t defined, the controller of the spell or ability chooses the value of X. All Xs on an object have the same value. A mana cost of means that you pay twice X.
How does mana reduction work with X spells?
You basically decide what you want X to be, calculate any taxes/discounts and then pay whatever amount you end up with. So you could indeed deal 5 with Rakdos out, play Endless One declaring X will equal 5 and then pay nothing for it.
How does Bolas Citadel work with X spells?
Whenever you pay an alternate cost to cast a spell, such as with Bolas’s Citadel, you can’t choose any value for X in the mana cost of the spell since you’re not paying the mana cost. In all of these cases, X is forced to be 0 and so Bolas does a pretty poor job of making these spells do anything.
Can you cast instants with bolas Citadel?
Bolas’s Citadel doesn’t allow you to cast anything for free. To play a Planeswalker card or a Creature card is to cast it as a spell. You will need to pay life instead of mana if you play one from the top of you deck.
Can a player cast a spell without paying its mana?
Whenever a player casts a spell from their hand, that player exiles it. If the player does, they may cast a spell from among other cards exiled with Knowledge Pool without paying its mana cost. If an opponent controls a Plains and you control a Mountain, you may cast this spell without paying its mana cost.
Is the converted mana cost of a spell with { X }?
X has indeed the same value on every instance on a card, and has the value chosen for it when it’s on the stack. If you chose X = 3, then the converted mana cost is 9 on the stack.
Can you cast a card from exile without paying mana cost?
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.) Tap target creature. It doesn’t untap during its controller’s next untap step. Rebound (If you cast this spell from your hand, exile it as it resolves.
How do you control creatures without paying mana?
Creatures you control have haste. Cascade, cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom of your library in a random order. Then do it again.)
