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.

Corrosive Ooze

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

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice this artifact: Draw a card.

Prizefight

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)
Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Wildsize

Target creature gets +2/+2 and gains trample until end of turn.
Draw a card.

Horned Helm

Equipped creature gets +1/+1 and has trample.
{G}{G}: Attach this Equipment to target creature you control.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Radical Idea

Draw a card.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

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.)

Wood Sage

{T}: Choose a creature card name. Reveal the top four cards of your library and put all of them with that name into your hand. Put the rest into your graveyard.

Merfolk Looter

Charge Through

Target creature gains trample until end of turn.
Draw a card.

Forest

Haunted Cloak

Equipped creature has vigilance, trample, and haste.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Command Tower

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

Arcane Signet

Thirsting Roots

Choose one —
• Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Windrider Wizard

Flying
Whenever you cast an instant, sorcery, or Wizard spell, you may draw a card. If you do, discard a card.

Counterspell

Tamiyo's Safekeeping

Target permanent you control gains hexproof and indestructible until end of turn. You gain 2 life. (A permanent 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.)

Rites of Refusal

Discard any number of cards. Counter target spell unless its controller pays {3} for each card discarded this way.

Careful Study

Larger Than Life

Target creature gets +4/+4 and gains trample until end of turn.

Compulsive Research

Target player draws three cards. Then that player discards two cards unless they discard a land card.

Piracy Charm

Choose one —
• Target creature gains islandwalk until end of turn. (It can't be blocked as long as defending player controls an Island.)
• Target creature gets +2/-1 until end of turn.
• Target player discards a card.

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.)

Vorrac Battlehorns

Equipped creature has trample and can't be blocked by more than one creature.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

King Harald's Revenge

Until end of turn, target creature gets +1/+1 for each creature you control and gains trample. It must be blocked this turn if able.

Island

Massive Might

Target creature gets +2/+2 and gains trample until end of turn.

Tolarian Winds

Discard all the cards in your hand, then draw that many cards.

Coral Net

Enchant green or white creature
Enchanted creature has "At the beginning of your upkeep, sacrifice this creature unless you discard a card."

Force Away

Return target creature to its owner's hand.
Ferocious — If you control a creature with power 4 or greater, you may draw a card. If you do, discard a card.

Vitality Charm

Choose one —
• Create a 1/1 green Insect creature token.
• Target creature gets +1/+1 and gains trample until end of turn.
• Regenerate target Beast.