Crobat

Flying, First Strike
Poison Touch 2 (Whenever Crobat becomes blocked, put two poison counters on blocking creature. At the beginning of its controller's upkeep, it gets -0/-1 until end of turn for each poison counter on it.)
Silent and swift in its four-winged flight, it bites down
on its prey before they realize what's happening. In a heartbeat, it drains their blood.