Essence Symbiote

Whenever a creature you control mutates, put a +1/+1 counter on that creature and you gain 2 life.

Unexpected Fangs

Put a +1/+1 counter and a lifelink counter on target creature.

Mysterious Egg

Whenever this creature mutates, put a +1/+1 counter on it.

Migratory Greathorn

Mutate {2}{G} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Whenever this creature mutates, search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Cavern Whisperer

Mutate {3}{B} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Menace (This creature can't be blocked except by two or more creatures.)
Whenever this creature mutates, each opponent discards a card.

Battlefly Swarm

Flying
{B}: Battlefly Swarm gains deathtouch until end of turn.

Air Bladder

Enchant creature
Enchanted creature has flying.
Enchanted creature can block only creatures with flying.

Feed the Clan

You gain 5 life.
Ferocious — You gain 10 life instead if you control a creature with power 4 or greater.

Jungle Hollow

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {B} or {G}.

Nightshade Dryad

Deathtouch
{T}: Add {C}.
{T}: Add one mana of any color.

Growth Cycle

Target creature gets +3/+3 until end of turn. It gets an additional +2/+2 until end of turn for each card named Growth Cycle in your graveyard.

Unlikely Aid

Target creature gets +2/+0 and gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)