Vampires know blood and the systems that carry it. And they know exactly where to strike to set it free.

Bright Reprisal

Destroy target attacking creature.
Draw a card.

Game Night

Ixalan

If the target creature is an illegal target by the time Bright Reprisal resolves, the entire spell doesn’t resolve. You won’t draw a card. If, on the other hand, the target is a legal target but isn’t destroyed (most likely because it has indestructible), you’ll draw a card.