Battlefield Robber

Prowl {p/b}(You may cast this for its prowl cost if you dealt combat damage to a player this turn with a Goblin or Rogue.)
Poisonous 2. (Whenever it deals combat damage to a player, that player gets two poison counters. A player with ten or more poison counters loses the game.)

Morbid — If a creature died this turn, Battlefield Robber can't be blocked.