When Contagion Clasp enters, put a -1/-1 counter on target creature. {4}, {T}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

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

When this creature enters, creatures your opponents control get -2/-2 until end of turn. Whenever a creature an opponent controls dies, that player loses 2 life.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) {T}: Add {C}.

Whenever a creature dies, if it had a -1/-1 counter on it, put a -1/-1 counter on target creature.

Put X -1/-1 counters on each creature. Shuffle Black Sun's Zenith into its owner's library.

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.