Rule 708.5

Anything that asks for a particular characteristic of a split card while it’s in a zone other than the stack gets two answers (one for each of the split card’s two halves). Anything that asks for a particular characteristic of a fused split spell gets two answers. Anything that asks for a particular characteristic of a split card while it’s a spell on the stack or that asks for the converted mana cost of a fused split spell gets one answer. Example: Spell Blast says “Counter target spell with converted mana cost X.” If a player wants to cast Spell Blast and choose the fused split spell Breaking/Entering, which has mana costs {U}{B} and {4}{B}{R}, as the target, that player must choose 8 as the value of X.

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