Equipped creature gets +1/+0 and has wither. (It deals damage to creatures in the form of -1/-1 counters.) Equip {2}

When Contagion Clasp enters the battlefield, 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.)

When Contagion Engine enters the battlefield, put a -1/-1 counter on each creature target player controls. {4}, {T}: Proliferate, then proliferate again. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

{4}, {T}: Put a -1/-1 counter on target creature.

Equipped creature gets +2/+2 and has infect. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Whenever Grafted Exoskeleton becomes unattached from a permanent, sacrifice that permanent. Equip {2}

Sacrifice a creature: Add one mana of any color.

Haste Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Chainbreaker enters the battlefield with two -1/-1 counters on it. {3}, {T}: Remove a -1/-1 counter from target creature.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) When Core Prowler dies, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) When Corpse Cur enters the battlefield, you may return target creature card with infect from your graveyard to your hand.

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

When Festering Mummy dies, you may put a -1/-1 counter on target creature.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Flying Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Sacrifice a creature: Flesh-Eater Imp gets +1/+1 until end of turn.

Sacrifice Fume Spitter: Put a -1/-1 counter on target creature.

Grim Poppet enters the battlefield with three -1/-1 counters on it. Remove a -1/-1 counter from Grim Poppet: Put a -1/-1 counter on another target creature.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Other creatures you control with infect get +1/+1. Whenever you cast a creature spell with infect, target player gets a poison counter.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) When Ichor Rats enters the battlefield, each player gets a poison counter.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Whenever Ichorclaw Myr becomes blocked, it gets +2/+2 until end of turn.

Wither (This deals damage to creatures in the form of -1/-1 counters.) When Lockjaw Snapper dies, put a -1/-1 counter on each creature with a -1/-1 counter on it.

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.) Whenever a Human deals damage to you, destroy it. Other non-Human creatures you control get +1/+1 and have undying. (When a creature with undying dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Wither (This deals damage to creatures in the form of -1/-1 counters.) Whenever a creature an opponent controls with a -1/-1 counter on it dies, you may return that card to the battlefield under your control.

Flying Wither (This deals damage to creatures in the form of -1/-1 counters.) Whenever Needle Specter deals combat damage to a player, that player discards that many cards.

{B/P}: Pestilent Souleater gains infect until end of turn. ({B/P} can be paid with either {B} or 2 life. A creature with infect deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

First strike, protection from red and from white Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Phyrexian Juggernaut attacks each combat if able.

({B/P} can be paid with either {B} or 2 life.) When Pith Driller enters the battlefield, put a -1/-1 counter on target creature.

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}.

Flying Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Whenever a source deals damage to Reaper of Sheoldred, that source's controller gets a poison counter.

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Whenever Septic Rats attacks, if defending player is poisoned, it gets +1/+1 until end of turn.

{T}: Put a -1/-1 counter on Serrated Biskelion and a -1/-1 counter on target creature.

Wither (This deals damage to creatures in the form of -1/-1 counters.)

Flying Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) {B}: Skithiryx, the Blight Dragon gains haste until end of turn. {B}{B}: Regenerate Skithiryx.

Flying Creatures with flying your opponents control get -1/-1.

Wither (This deals damage to creatures in the form of -1/-1 counters.)

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) {B}: Regenerate Toxic Nim.

{B}: Vector Asp gains infect until end of turn. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Flying Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) Whenever Whispering Specter deals combat damage to a player, you may sacrifice it. If you do, that player discards a card for each poison counter they have.

Enchant creature Enchanted creature gets -1/-1 and can't block.

At the beginning of your upkeep, destroy target creature with a -1/-1 counter on it.

Enchant player Creatures enchanted player controls get -1/-1.

{2}{B}{B}: Put a -1/-1 counter on target creature.

Enchant creature Enchanted creature has infect. At the beginning of your upkeep, put a -1/-1 counter on enchanted creature. When Glistening Oil is put into a graveyard from the battlefield, return Glistening Oil to its owner's hand.

Creature tokens get -1/-1.

Whenever you put one or more -1/-1 counters on a creature, create that many 1/1 black Insect creature tokens.

Put a -1/-1 counter on target creature, then proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Put a -1/-1 counter on target creature. Draw a card.

Distribute two -1/-1 counters among one or two target creatures.

Put three -1/-1 counters on target creature. Its controller loses 3 life unless they sacrifice another nonland permanent or discards a card.

{2}, {T}: Add {B} for each Swamp you control.

{T}: Add {C}. {1}: Inkmoth Nexus becomes a 1/1 Phyrexian Blinkmoth artifact creature with flying and infect until end of turn. It's still a land. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

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.