Manaplasm | Magic: The Gathering
Formats Manaplasm is Legal in
Official Oracle Text for Manaplasm
Official Rulings for Manaplasm
10/1/2008 : While a spell with in its cost is on the stack, its converted mana cost takes the chosen value of X into account. For example, if you cast Blaze (a spell with the mana cost ) and choose a value of 5 for that X, then your Manaplasm will get +6/+6 until end of turn.