Kirijo Nezujo, Nezumi Assassin

Ninjutsu {3}{u}{b}
When Kirijo, Nezumi Assassin deals combat
damage to a player, choose one:
•Search your library for a rat or vehicle whose
converted mana cost is equal to or less
than the damage dealt, add it to your hand.
•Destroy target creature whose toughness
is equal to or less than the damage dealt.