Battlegate Mimic

Whenever you cast a spell that's both red and white, Battlegate Mimic has base power and toughness 4/2 until end of turn and gains first strike until end of turn.

Webweaver Changeling

Changeling (This card is every creature type.)
Reach
When Webweaver Changeling enters, if there are three or more creature cards in your graveyard, you gain 5 life.

Universal Automaton

Changeling (This card is every creature type.)

Kodama's Reach

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.

Fire-Belly Changeling

Changeling (This card is every creature type.)
{R}: Fire-Belly Changeling gets +1/+0 until end of turn. Activate no more than twice each turn.

Bloodline Pretender

Changeling (This card is every creature type.)
As Bloodline Pretender enters, choose a creature type.
Whenever another creature you control of the chosen type enters, put a +1/+1 counter on Bloodline Pretender.

Kaheera, the Orphanguard

Companion — Each creature card in your starting deck is a Cat, Elemental, Nightmare, Dinosaur, or Beast card. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
Vigilance
Each other creature you control that's a Cat, Elemental, Nightmare, Dinosaur, or Beast gets +1/+1 and has vigilance.

Cultivate

Shields of Velis Vel

Changeling (This card is every creature type.)
Creatures target player controls get +0/+1 and gain all creature types until end of turn.

Black Market Tycoon

At the beginning of your upkeep, Black Market Tycoon deals 2 damage to you for each Treasure you control.
{T}: Create a Treasure token.

Feline Sovereign

Other Cats you control get +1/+1 and have protection from Dogs.
Whenever one or more Cats you control deal combat damage to a player, destroy up to one target artifact or enchantment that player controls.

Isamaru, Hound of Konda

Chameleon Colossus

Changeling (This card is every creature type.)
Protection from black
{2}{G}{G}: Chameleon Colossus gets +X/+X until end of turn, where X is its power.

Blades of Velis Vel

Changeling (This card is every creature type.)
Up to two target creatures each get +2/+0 and gain all creature types until end of turn.

Release the Dogs

Create four 1/1 white Dog creature tokens.

Irregular Cohort

Changeling (This card is every creature type.)
When Irregular Cohort enters, create a 2/2 colorless Shapeshifter creature token with changeling.

Impostor of the Sixth Pride

Pack Leader

Other Dogs you control get +1/+1.
Whenever Pack Leader attacks, prevent all combat damage that would be dealt this turn to Dogs you control.

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Realmwalker

Changeling (This card is every creature type.)
As Realmwalker enters, choose a creature type.
You may look at the top card of your library any time.
You may cast creature spells of the chosen type from the top of your library.

Alpine Watchdog

Vigilance (Attacking doesn't cause this creature to tap.)

Jetmir, Nexus of Revels

Creatures you control get +1/+0 and have vigilance as long as you control three or more creatures.
Creatures you control also get +1/+0 and have trample as long as you control six or more creatures.
Creatures you control also get +1/+0 and have double strike as long as you control nine or more creatures.

Woodland Changeling

Crib Swap

Changeling (This card is every creature type.)
Exile target creature. Its controller creates a 1/1 colorless Shapeshifter creature token with changeling.

Avian Changeling

Changeling (This card is every creature type.)
Flying

Arcbound Mouser

Lifelink
Modular 1 (This creature enters with a +1/+1 counter on it. When it dies, you may put its +1/+1 counters on target artifact creature.)

Mirror Entity

Changeling (This card is every creature type.)
{X}: Until end of turn, creatures you control have base power and toughness X/X and gain all creature types.

Getting

Rin and Seri, Inseparable

Whenever you cast a Dog spell, create a 1/1 green Cat creature token.
Whenever you cast a Cat spell, create a 1/1 white Dog creature token.
{R}{G}{W}, {T}: Rin and Seri, Inseparable deals damage to any target equal to the number of Dogs you control. You gain life equal to the number of Cats you control.

Taurean Mauler

Changeling (This card is every creature type.)
Whenever an opponent casts a spell, you may put a +1/+1 counter on this creature.