Guac & Marshmallow Pizza

Flash
When this artifact enters, target creature gets +2/+2 until end of turn. Untap it.
{2}, {T}, Sacrifice this artifact: You gain 3 life.

Novel Nunchaku

When this Equipment enters, attach it to target creature you control. When you do, equipped creature fights up to one target creature an opponent controls. (Each deals damage equal to its power to the other.)
Equipped creature gets +1/+1 and has trample.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Primordial Pachyderm

Reach, trample
When this creature enters, you gain 2 life.

Mona Lisa, Ever Adaptable

Whenever a player casts a creature spell, you create a Mutagen token. (It's an artifact with "{1}, {T}, Sacrifice this token: Put a +1/+1 counter on target creature. Activate only as a sorcery.")

Mikey & Mona, Mutant Sitters

When Mikey & Mona enter, choose one or both. Each mode must target a different player.
• Target player chooses a creature they control and puts two +1/+1 counters on it.
• Target player returns a creature or land card from their graveyard to their hand.

Frog Butler

Deathtouch
{T}: Add one mana of any color.
{2}: This creature gains reach until end of turn.

Zoo Escapees

When this creature leaves the battlefield, create a Mutagen token. (It's an artifact with "{1}, {T}, Sacrifice this token: Put a +1/+1 counter on target creature. Activate only as a sorcery.")

Turtle Tracks

Any number of target players may each search their library for a basic land card, put it onto the battlefield under their control, then shuffle.

Michelangelo, On the Scene

Trample (This creature can deal excess combat damage to the player it's attacking.)
Michelangelo enters with a +1/+1 counter on him for each land you control.
When Michelangelo dies, return this card to your hand.

Prehistoric Turtlesaurus

This spell costs {1} less to cast if you control a creature with a +1/+1 counter on it.
Vigilance (Attacking doesn't cause this creature to tap.)

Study the Classics

Put a +1/+1 counter on target creature, then double the number of +1/+1 counters on it. You gain life equal to the number of +1/+1 counters on that creature.

Michelangelo, Game Master

Disappear — At the beginning of your end step, if a permanent left the battlefield under your control this turn, put a +1/+1 counter on Michelangelo.

Michelangelo, Mutant BFF

Each creature you control with a counter on it can't be blocked by more than one creature.
Whenever Michelangelo enters or attacks, create a Mutagen token. (It's an artifact with "{1}, {T}, Sacrifice this token: Put a +1/+1 counter on target creature. Activate only as a sorcery.")

Ragamuffin Raptor

When this creature enters, return up to one target creature or Food card from your graveyard to your hand.

Foe-liage

Whenever a land enters during your turn, put a +1/+1 counter on this creature.

Cowabunga!

Look at the top four cards of your library. You may reveal a Mutant, Ninja, Turtle, or land card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Slithering Cryptid

When this creature enters, create a Mutagen token. (It's an artifact with "{1}, {T}, Sacrifice this token: Put a +1/+1 counter on target creature. Activate only as a sorcery.")

Tenderize

Target creature you control deals damage equal to its power to target creature an opponent controls.

Mona Lisa, Science Geek

Reach
{T}: Add X mana of any one color, where X is Mona Lisa's power.

Forest

Definitely Not a Turtle

When this creature dies, look at the top six cards of your library. You may reveal a land or legendary Turtle card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.