Text (SA): Choose one or both - ~this~ deals 3 damage to target creature with flying; and/or ~this~ deals 3 damage to target creature without flying.
When playing this spell, first choose the mode. Then treat the card as if its text only had the text from the chosen mode. [Shards of Alara FAQ 2008/09/23]
You can't choose a mode unless there's a legal target for that mode. [Shards of Alara FAQ 2008/09/23]
Note - Also see Modal Spells and Abilities, Rule G13.13.
