Vat Emergence

Put target creature card from a graveyard onto the battlefield under your control. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Necrogen Communion

Enchant creature you control
Enchanted creature has toxic 2. (Players dealt combat damage by it also get two poison counters.)
When enchanted creature dies, return that card to the battlefield under your control.

Venomous Brutalizer

Toxic 3 (Players dealt combat damage by this creature also get three poison counters.)
When Venomous Brutalizer enters, you may pay {1}{G}. If you do, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Dross Skullbomb

{1}, Sacrifice Dross Skullbomb: Draw a card.
{2}{B}, Sacrifice Dross Skullbomb: Return target creature card from your graveyard to your hand. Draw a card. Activate only as a sorcery.

Feed the Infection

You draw three cards and you lose 3 life.
Corrupted — Each opponent who has three or more poison counters loses 3 life.

Green Sun's Twilight

Reveal the top X plus one cards of your library. Choose a creature card and/or a land card from among them. Put those cards into your hand and the rest on the bottom of your library in a random order. If X is 5 or more, instead put the chosen cards onto the battlefield or into your hand and the rest on the bottom of your library in a random order.

Whisper of the Dross

Target creature gets -1/-1 until end of turn. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Swamp

Branchblight Stalker

Toxic 2 (Players dealt combat damage by this creature also get two poison counters.)

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Maze Skullbomb

{1}, Sacrifice Maze Skullbomb: Draw a card.
{2}{G}, Sacrifice Maze Skullbomb: Target creature you control gets +3/+3 and gains trample until end of turn. Draw a card. Activate only as a sorcery.

Titanic Growth

Target creature gets +4/+4 until end of turn.

Forest

Sheoldred's Headcleaver

Menace
Toxic 2 (Players dealt combat damage by this creature also get two poison counters.)

Atraxa's Skitterfang

Atraxa's Skitterfang enters with three oil counters on it.
At the beginning of combat on your turn, you may remove an oil counter from Atraxa's Skitterfang. When you do, target creature you control gains your choice of flying, vigilance, deathtouch, or lifelink until end of turn.

Tyrranax Atrocity

Haste
Toxic 3 (Players dealt combat damage by this creature also get three poison counters.)

Infectious Bite

Target creature you control deals damage equal to its power to target creature you don't control. Each opponent gets a poison counter.

Annihilating Glare

As an additional cost to cast this spell, pay {4} or sacrifice an artifact or creature.
Destroy target creature or planeswalker.

Adaptive Sporesinger

Vigilance
When Adaptive Sporesinger enters, choose one —
• Target creature gets +2/+2 and gains vigilance until end of turn.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Offer Immortality

Target creature gains deathtouch and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Plague Nurse

Toxic 2
{2}{G}: Each other creature you control with toxic gains toxic 1 until end of turn. Activate only once each turn. (A player dealt combat damage by a creature with toxic also gets poison counters equal to that creature's total toxic value.)

Necrogen Rotpriest

Toxic 2 (Players dealt combat damage by this creature also get two poison counters.)
Whenever a creature you control with toxic deals combat damage to a player, that player gets an additional poison counter.
{1}{B}{G}: Target creature you control with toxic gains deathtouch until end of turn.