Forest

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.)

Skrelv's Hive

At the beginning of your upkeep, you lose 1 life and create a 1/1 colorless Phyrexian Mite artifact creature token with toxic 1 and "This token can't block."
Corrupted — As long as an opponent has three or more poison counters, creatures you control with toxic have lifelink.

Ossification

Enchant basic land you control
When this Aura enters, exile target creature or planeswalker an opponent controls until this Aura leaves the battlefield.

Flensing Raptor

Flying
Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
When this creature enters, another target creature you control with toxic gets +1/+1 and gains flying until end of turn.

Tyvar's Stand

Target creature you control gets +X/+X and gains hexproof and indestructible until end of turn. (A creature with hexproof and indestructible can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Porcelain Zealot

At the beginning of combat on your turn, target creature you control gets +1/+1 until end of turn. If that creature has toxic, instead it gets +2/+2 until end of turn.

Basilica Shepherd

Flying
When this creature enters, create two 1/1 colorless Phyrexian Mite artifact creature tokens with toxic 1 and "This token can't block." (Players dealt combat damage by them also get a poison counter.)

Incisor Glider

Flying
Corrupted — Whenever this creature attacks, if an opponent has three or more poison counters, creatures you control get +1/+1 until end of turn.

Paladin of Predation

Toxic 6 (Players dealt combat damage by this creature also get six poison counters.)
This creature can't be blocked by creatures with power 2 or less.

Carnivorous Canopy

Destroy target artifact, enchantment, or creature with flying. If that permanent's mana value was 3 or less, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Graaz, Unstoppable Juggernaut

Juggernauts you control attack each combat if able.
Juggernauts you control can't be blocked by Walls.
Other creatures you control have base power and toughness 5/3 and are Juggernauts in addition to their other creature types.

Infested Fleshcutter

Equipped creature gets +2/+0.
Whenever equipped creature attacks, create a 1/1 colorless Phyrexian Mite artifact creature token with toxic 1 and "This token can't block." (Players dealt combat damage by it also get a poison counter.)
Equip {2}{W}

Armored Scrapgorger

This creature gets +3/+0 as long as it has three or more oil counters on it.
{T}: Add one mana of any color.
Whenever this creature becomes tapped, exile target card from a graveyard and put an oil counter on this creature.

Charge of the Mites

Choose one —
• Charge of the Mites deals damage equal to the number of creatures you control to target creature or planeswalker.
• Create two 1/1 colorless Phyrexian Mite artifact creature tokens with toxic 1 and "This token can't block." (Players dealt combat damage by them also get a poison counter.)

Duelist of Deep Faith

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
During your turn, this creature has first strike.

Ichorspit Basilisk

Deathtouch
Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)

Ruthless Predation

Target creature you control gets +1/+2 until end of turn. It fights target creature you don't control. (Each deals damage equal to its power to the other.)

Plains

Crawling Chorus

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
When this creature dies, create a 1/1 colorless Phyrexian Mite artifact creature token with toxic 1 and "This token can't block."

Vanish into Eternity

This spell costs {3} more to cast if it targets a creature.
Exile target nonland permanent.

Jawbone Duelist

Double strike
Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)

Hexgold Hoverwings

For Mirrodin! (When this Equipment enters, create a 2/2 red Rebel creature token, then attach this to it.)
Equipped creature has flying.
Creatures you control that are equipped get +1/+0.
Equip {2}{W}

Tyrranax Atrocity

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