2006-07-15
A card that's already revealed for another cost or because of an effect can be revealed to pay this cost.
2006-07-15
Each card that's revealed to pay the cost remains revealed until the ability leaves the stack.
2006-07-15
If one of the cards that's revealed to pay the cost leaves its owner's hand before the ability resolves, it stops being revealed, but the value of X is not affected.