Become Anonymous

Exile target nontoken creature you own and the top two cards of your library in a face-down pile, shuffle that pile, then cloak those cards. They enter tapped. (To cloak a card, put it onto the battlefield face down as a 2/2 creature with ward {2}. Turn it face up any time for its mana cost if it's a creature card.)

Forest

Snakeform

Until end of turn, target creature loses all abilities and becomes a green Snake with base power and toughness 1/1.
Draw a card.

Afterlife

Destroy target creature. It can't be regenerated. Its controller creates a 1/1 white Spirit creature token with flying.

Wildsize

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

Slip Out the Back

Put a +1/+1 counter on target creature. It phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)

Aether Mutation

Return target creature to its owner's hand. Create X 1/1 green Saproling creature tokens, where X is that creature's mana value.

Plains

Bottle-Cap Blast

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Bottle-Cap Blast deals 5 damage to any target. If excess damage was dealt to a permanent this way, create that many tapped Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Mountain

Absorb Identity

Return target creature to its owner's hand. You may have Shapeshifters you control become copies of that creature until end of turn.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Incongruity

Exile target creature. That creature's controller creates a 3/3 green Frog Lizard creature token.

Incubation

Look at the top five cards of your library. You may reveal a creature card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Incubation // Incongruity

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Aggressive Biomancy

Create X tokens that are copies of target creature you control, except they have "When this creature enters, it fights up to one target creature you don't control."

Ink-Treader Nephilim

Whenever a player casts an instant or sorcery spell, if that spell targets only Ink-Treader Nephilim, copy the spell for each other creature that spell could target. Each copy targets a different one of those creatures.

Gift of the Viper

Put a +1/+1 counter, a reach counter, and a deathtouch counter on target creature. Untap it.

Lightning Helix

Lightning Helix deals 3 damage to any target and you gain 3 life.

Invert Polarity

Choose target spell, then flip a coin. If you win the flip, gain control of that spell and you may choose new targets for it. If you lose the flip, counter that spell.

Aggressive Instinct

Target creature you control deals damage equal to its power to target creature you don't control.

Aether Helix

Return target permanent to its owner's hand. Return target permanent card from your graveyard to your hand.

Misthios's Fury

Misthios's Fury deals 3 damage to target creature. If you control an Equipment, Misthios's Fury also deals 2 damage to that creature's controller.

Intervention

Intervention deals 3 damage to any target and you gain 3 life.

Integrity

Target creature gets +2/+2 until end of turn.

Integrity // Intervention

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Island

Aether Gust

Choose target spell or permanent that's red or green. Its owner puts it on the top or bottom of their library.

Eldritch Immunity

Target creature you control gains protection from each color until end of turn.
Overload {4}{C} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")