Barony Werebat

Flying, Mangle (At the end of the Cleanup step,
put a number of -1/-1 tokens on each creature
equal to the damage Barony Werebat caused it.)
At the beginning of your end step, you lose 1 life.
"Most of the experiments the Baron's minions
undertook at his direction went wrong. Only a few
survived and escaped to be menaces in the wild.
Feeding against his will."