Arrow Storm deals 4 damage to target creature or player. Raid — If you attacked with a creature this turn, instead Arrow Storm deals 5 damage to that creature or player and the damage can't be prevented.
First the thunder, then the rain.
098 KTK • ENSteve Prescott
™ & © 1993—2014 Wizards of the Coast
Legal in: Modern,Khans of Tarkir Block,Legacy,Vintage,Commander
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9/20/2014 Raid abilities care only that you attacked with a creature. It doesn’t matter how many creatures you attacked with, or which opponent or planeswalker controlled by an opponent those creatures attacked. 9/20/2014 Raid abilities evaluate the entire turn to see if you attacked with a creature. That creature doesn’t have to still be on the battlefield. Similarly, the player or planeswalker it attacked doesn’t have to still be in the game or on the battlefield, respectively.