Valiant Changeling

This spell costs {1} less to cast for each creature type among creatures you control. This effect can't reduce the amount of mana this spell costs by more than {5}.
Changeling (This card is every creature type.)
Double strike

Knight Exemplar

First strike (This creature deals combat damage before creatures without first strike.)
Other Knight creatures you control get +1/+1 and have indestructible. (Damage and effects that say "destroy" don't destroy them.)

Amoeboid Changeling

Changeling (This card is every creature type.)
{T}: Target creature gains all creature types until end of turn.
{T}: Target creature loses all creature types until end of turn.

Fabricate

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

Vanquisher's Banner

As Vanquisher's Banner enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
Whenever you cast a creature spell of the chosen type, draw a card.

Coat of Arms

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Goblin Warriors and a Goblin Shaman are on the battlefield, each gets +2/+2.)

Irregular Cohort

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

Ego Erasure

Changeling (This card is every creature type.)
Creatures target player controls get -2/-0 and lose all creature types until end of turn.

Command Tower

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

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Plains

Peer Pressure

Choose a creature type. If you control more creatures of that type than each other player, you gain control of all creatures of that type. (This effect lasts indefinitely.)

Island

Swamp

Drafna's Restoration

Put any number of target artifact cards from target player's graveyard on top of their library in any order.

Changeling Outcast

Changeling (This card is every creature type.)
Changeling Outcast can't block and can't be blocked.

Edifice of Authority

{1}, {T}: Target creature can't attack this turn. Put a brick counter on Edifice of Authority.
{1}, {T}: Until your next turn, target creature can't attack or block and its activated abilities can't be activated. Activate only if there are three or more brick counters on Edifice of Authority.

Karona, False God

Haste
At the beginning of each player's upkeep, that player untaps Karona, False God and gains control of it.
Whenever Karona attacks, creatures of the creature type of your choice get +3/+3 until end of turn.

Distant Melody

Choose a creature type. Draw a card for each permanent you control of that type.

Progenitor Mimic

You may have Progenitor Mimic enter as a copy of any creature on the battlefield, except it has "At the beginning of your upkeep, if this creature isn't a token, create a token that's a copy of this creature."

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)