Whenever a creature is put into a graveyard from play. if it had a -1/-1 counter on it. put a -1/-1 counter on target creature.

Black creatures you control have wither. (They deal damage to creatures in the form of -1/-1 counters.)

Corrupt deals damage equal to the number of Swamps you control to target creature or player. You gain life equal to the damage dealt this way.

power and toughness are each equal to the number of black permanents you control.

Whenever Hollowsage becomes untapped. you may have target player discard a card.

Put a -1/-1 counter on target creature. two -1/-1 counters on another target creature. and three -1/-1 counters on a third target creature.