Chillbringer Dementor

Flying, shaded (This spell cannot be countered.)

At the beginning of your upkeep, you may pay 2
life. If you don't, put a -1/-1 counter on
Chillbringer Dementor.
Whenever Chillbringer Dementor attacks, all
creatures that the player it's attacking controls
get -1/-1 until end of turn.