MM: Venomous Breath, Instant 3G Choose target creature. At this turn's next end of combat, destroy all creatures that blocked or were blocked by it this...

Venomous Breath

Choose target creature. At this turn's next end of combat, destroy all creatures that blocked or were blocked by it this turn.

10/4/2004 It affects creatures that had blocked the target when this spell resolves, even if they are no longer blocking the creature.