Experiment One

Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
Remove two +1/+1 counters from Experiment One: Regenerate Experiment One. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Corrosive Ooze

Whenever Corrosive Ooze blocks or becomes blocked by an equipped creature, destroy all Equipment attached to that creature at end of combat.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Green Slime

Flash
When Green Slime enters, counter target activated or triggered ability from an artifact or enchantment source. If a permanent's ability is countered this way, destroy that permanent.
Foretell {G} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Gluttonous Slime

Flash
Devour 1 (As this enters, you may sacrifice any number of creatures. This creature enters with that many +1/+1 counters on it.)

Ooze Flux

{1}{G}, Remove one or more +1/+1 counters from among creatures you control: Create an X/X green Ooze creature token, where X is the number of +1/+1 counters removed this way.

Predator Ooze

Indestructible (Damage and effects that say "destroy" don't destroy this creature.)
Whenever this creature attacks, put a +1/+1 counter on it.
Whenever a creature dealt damage by this creature this turn dies, put a +1/+1 counter on this creature.

Biogenic Ooze

When Biogenic Ooze enters, create a 2/2 green Ooze creature token.
At the beginning of your end step, put a +1/+1 counter on each Ooze you control.
{1}{G}{G}{G}: Create a 2/2 green Ooze creature token.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Slurrk, All-Ingesting

Slurrk, All-Ingesting enters with five +1/+1 counters on it.
Whenever Slurrk or another creature you control dies, if it had a +1/+1 counter on it, put a +1/+1 counter on each creature you control that has a +1/+1 counter on it.
Partner (You can have two commanders if both have partner.)

Mitotic Slime

When Mitotic Slime dies, create two 2/2 green Ooze creature tokens. They have "When this creature dies, create two 1/1 green Ooze creature tokens."

Miming Slime

Create an X/X green Ooze creature token, where X is the greatest power among creatures you control.

Oran-Rief Ooze

When Oran-Rief Ooze enters, put a +1/+1 counter on target creature you control.
Whenever Oran-Rief Ooze attacks, put a +1/+1 counter on each attacking creature with a +1/+1 counter on it.

Splitting Slime

{4}{G}{G}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)
When Splitting Slime becomes monstrous, create a token that's a copy of Splitting Slime. (The token has no counters and isn't monstrous.)

Printlifter Ooze

Deathtouch
Whenever Printlifter Ooze or another creature you control is turned face up, create a 0/0 green Ooze creature token with trample. The token enters with X +1/+1 counters on it, where X is the number of other creatures you control.
Disguise {3}{G}

Inexorable Blob

Delirium — Whenever Inexorable Blob attacks, if there are four or more card types among cards in your graveyard, create a 3/3 green Ooze creature token that's tapped and attacking.

Scavenging Ooze

{G}: Exile target card from a graveyard. If it was a creature card, put a +1/+1 counter on this creature and you gain 1 life.

Slime Molding

Aeve, Progenitor Ooze

Storm (When you cast this spell, copy it for each spell cast before it this turn. Copies become tokens.)
Aeve, Progenitor Ooze isn't legendary if it's a token.
Aeve enters with a +1/+1 counter on it for each other Ooze you control.

Biowaste Blob

Oozes you control get +1/+1.
At the beginning of your upkeep, if you control a commander, create a token that's a copy of Biowaste Blob.

Slime Against Humanity

Create a 0/0 green Ooze creature token with trample. Put X +1/+1 counters on it, where X is two plus the total number of cards you own in exile and in your graveyard that are Oozes or are named Slime Against Humanity.
A deck can have any number of cards named Slime Against Humanity.

Consuming Blob

Consuming Blob's power is equal to the number of card types among cards in your graveyard and its toughness is equal to that number plus 1.
At the beginning of your end step, create a green Ooze creature token with "This creature's power is equal to the number of card types among cards in your graveyard and its toughness is equal to that number plus 1."

Ravenous Slime

Ravenous Slime can't be blocked by creatures with power 2 or less.
If a creature an opponent controls would die, instead exile it and put a number of +1/+1 counters equal to that creature's power on Ravenous Slime.

Ochre Jelly

Trample
Ochre Jelly enters with X +1/+1 counters on it.
Split — When Ochre Jelly dies, if it had two or more +1/+1 counters on it, create a token that's a copy of it at the beginning of the next end step. The token enters with half that many +1/+1 counters on it, rounded down.

Temperamental Oozewagg

{2}{G}: Adapt 2. (If this creature has no +1/+1 counters on it, put two +1/+1 counters on it.)
Modified creatures you control have trample. (Equipment, Auras you control, and counters are modifications.)

Forest

Acidic Slime

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
When Acidic Slime enters, destroy target artifact, enchantment, or land.

Bioplasm

Whenever Bioplasm attacks, exile the top card of your library. If it's a creature card, Bioplasm gets +X/+Y until end of turn, where X is the exiled creature card's power and Y is its toughness.