Teivel, Death Spreader

Partner with Hapatra, Vizier of Poisons (When
this creature enters the battlefield, target player may
put Hapatra, Vizier of Poisons into their hand from
their library, then shuffle.)
Whenever a creature deals combat damage to a
player, you may pay {b}{g}. If you do, move any
number of -1/-1 counters from it onto target
creature that player controls.