Door of Destinies

As Door of Destinies enters, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

Forest

Risen Reef

Whenever Risen Reef or another Elemental you control enters, look at the top card of your library. If it's a land card, you may put it onto the battlefield tapped. If you don't put the card onto the battlefield, put it into your hand.

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.)

Skeletal Changeling

Changeling (This card is every creature type.)
{1}{B}: Regenerate Skeletal Changeling.

Counterspell

Whelming Wave

Return all creatures to their owners' hands except for Krakens, Leviathans, Octopuses, and Serpents.

Lord of Atlantis

Other Merfolk get +1/+1 and have islandwalk. (They can't be blocked as long as defending player controls an Island.)

Island

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.

Gemhide Sliver

All Slivers have "{T}: Add one mana of any color."

Steam Vents

({T}: Add {U} or {R}.)
As Steam Vents enters, you may pay 2 life. If you don't, it enters tapped.

Avian Changeling

Changeling (This card is every creature type.)
Flying

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.

Lord of the Unreal

Illusion creatures you control get +1/+1 and have hexproof. (They can't be the targets of spells or abilities your opponents control.)

Birthing Boughs

{4}, {T}: Create a 2/2 colorless Shapeshifter creature token with changeling. (It has every creature type.)

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.)

Harsh Mercy

Each player chooses a creature type. Destroy all creatures that aren't of a type chosen this way. They can't be regenerated.

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.

Eladamri's Call

Search your library for a creature card, reveal that card, put it into your hand, then shuffle.

Mirari's Wake

Creatures you control get +1/+1.
Whenever you tap a land for mana, add one mana of any type that land produced.

Shapesharer

Changeling (This card is every creature type.)
{2}{U}: Target Shapeshifter becomes a copy of target creature until your next turn.

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.

Thought Vessel

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

Death Baron

Skeletons you control and other Zombies you control get +1/+1 and have deathtouch. (Any amount of damage they deal to a creature is enough to destroy it.)

Changeling Outcast

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

Mass Appeal

Watery Grave

({T}: Add {U} or {B}.)
As Watery Grave enters, you may pay 2 life. If you don't, it enters tapped.

Woodland Changeling

Changeling (This card is every creature type.)

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.

The Great Henge

This spell costs {X} less to cast, where X is the greatest power among creatures you control.
{T}: Add {G}{G}. You gain 2 life.
Whenever a nontoken creature you control enters, put a +1/+1 counter on it and draw a card.

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.

Explosive Vegetation

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Arcane Signet

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

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

Kindred Discovery

As Kindred Discovery enters, choose a creature type.
Whenever a creature you control of the chosen type enters or attacks, draw a card.

Plains

Cairn Wanderer

Changeling (This card is every creature type.)
As long as a creature card with flying is in a graveyard, Cairn Wanderer has flying. The same is true for fear, first strike, double strike, deathtouch, haste, landwalk, lifelink, protection, reach, trample, shroud, and vigilance.

Sol Ring

Dragon's Hoard

Whenever a Dragon you control enters, put a gold counter on Dragon's Hoard.
{T}, Remove a gold counter from Dragon's Hoard: Draw a card.
{T}: Add one mana of any color.

Sacred Foundry

({T}: Add {R} or {W}.)
As Sacred Foundry enters, you may pay 2 life. If you don't, it enters tapped.

Mountain

Moonglove Changeling

Changeling (This card is every creature type.)
{B}: Moonglove Changeling gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy that creature.)

Blood Crypt

({T}: Add {B} or {R}.)
As Blood Crypt enters, you may pay 2 life. If you don't, it enters tapped.

Irregular Cohort

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

Temple Garden

({T}: Add {G} or {W}.)
As Temple Garden enters, you may pay 2 life. If you don't, it enters tapped.

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Fierce Guardianship

If you control a commander, you may cast this spell without paying its mana cost.
Counter target noncreature spell.

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.

Orah, Skyclave Hierophant

Lifelink
Whenever Orah, Skyclave Hierophant or another Cleric you control dies, return target Cleric card with lesser mana value from your graveyard to the battlefield.

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Reaper King

({2/W} can be paid with any two mana or with {W}. This card's mana value is 10.)
Other Scarecrow creatures you control get +1/+1.
Whenever another Scarecrow you control enters, destroy target permanent.

Universal Automaton

Unsettled Mariner

Changeling (This card is every creature type.)
Whenever you or a permanent you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {1}.

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.

Ravos, Soultender

Flying
Other creatures you control get +1/+1.
At the beginning of your upkeep, you may return target creature card from your graveyard to your hand.
Partner (You can have two commanders if both have partner.)

Command Tower

Liliana's Contract

When Liliana's Contract enters, you draw four cards and you lose 4 life.
At the beginning of your upkeep, if you control four or more Demons with different names, you win the game.

Herald's Horn

As Herald's Horn enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

March from the Tomb

Return any number of target Ally creature cards with total mana value 8 or less from your graveyard to the battlefield.

Drogskol Captain

Flying
Other Spirit creatures you control get +1/+1 and have hexproof. (They can't be the targets of spells or abilities your opponents control.)

Magda, Brazen Outlaw

Other Dwarves you control get +1/+0.
Whenever a Dwarf you control becomes tapped, create a Treasure token.
Sacrifice five Treasures: Search your library for an artifact or Dragon card, put that card onto the battlefield, then shuffle.

Cultivate

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.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Graveshifter

Changeling (This card is every creature type.)
When Graveshifter enters, you may return target creature card from your graveyard to your hand.

Sliver Hivelord

Sliver creatures you control have indestructible. (Damage and effects that say "destroy" don't destroy them.)

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Impostor of the Sixth Pride

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.

Godless Shrine

({T}: Add {W} or {B}.)
As Godless Shrine enters, you may pay 2 life. If you don't, it enters tapped.

Hallowed Fountain

({T}: Add {W} or {U}.)
As Hallowed Fountain enters, you may pay 2 life. If you don't, it enters tapped.

Breeding Pool

({T}: Add {G} or {U}.)
As Breeding Pool enters, you may pay 2 life. If you don't, it enters tapped.

Swamp

Reliquary Tower

Venomous Changeling

Changeling (This card is every creature type.)
Deathtouch

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Stomping Ground

({T}: Add {R} or {G}.)
As Stomping Ground enters, you may pay 2 life. If you don't, it enters tapped.

Kodama's Reach

Notorious Throng

Prowl {5}{U} (You may cast this for its prowl cost if you dealt combat damage to a player this turn with a Rogue.)
Create X 1/1 black Faerie Rogue creature tokens with flying, where X is the damage dealt to your opponents this turn. If this spell's prowl cost was paid, take an extra turn after this one.

Overgrown Tomb

({T}: Add {B} or {G}.)
As Overgrown Tomb enters, you may pay 2 life. If you don't, it enters tapped.

Thwart the Grave

This spell costs {1} less to cast for each creature in your party. (Your party consists of up to one each of Cleric, Rogue, Warrior, and Wizard.)
Return target creature card and up to one target Cleric, Rogue, Warrior, or Wizard creature card from your graveyard to the battlefield.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Mothdust Changeling

Changeling (This card is every creature type.)
Tap an untapped creature you control: Mothdust Changeling gains flying until end of turn.

Morophon, the Boundless

Changeling (This card is every creature type.)
As Morophon, the Boundless enters, choose a creature type.
Spells of the chosen type you cast cost {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.
Other creatures you control of the chosen type get +1/+1.