Arcane Adaptation

As Arcane Adaptation enters, choose a creature type.
Creatures you control are the chosen type in addition to their other types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.

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.

Command Tower

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

Baldur's Gate

{T}: Add {C}.
{2}, {T}: Add X mana of any one color, where X is the number of other Gates you control.

Chasm Guide

Rally — Whenever Chasm Guide or another Ally you control enters, creatures you control gain haste until end of turn.

Kazuul Warlord

Whenever Kazuul Warlord or another Ally you control enters, you may put a +1/+1 counter on each Ally creature you control.

Manor Gate

Manor Gate enters tapped.
As Manor Gate enters, choose a color other than green.
{T}: Add {G} or one mana of the chosen color.

Ondu Cleric

Whenever Ondu Cleric or another Ally you control enters, you may gain life equal to the number of Allies you control.

Gateway Plaza

Gateway Plaza enters tapped.
When Gateway Plaza enters, sacrifice it unless you pay {1}.
{T}: Add one mana of any color.

Sword Coast Sailor

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, this creature can't be blocked this turn."

Sea Gate Loremaster

{T}: Draw a card for each Ally you control.

Orzhov Guildgate

Orzhov Guildgate enters tapped.
{T}: Add {W} or {B}.

Guild Summit

When Guild Summit enters, you may tap any number of untapped Gates you control. Draw a card for each Gate tapped this way.
Whenever a Gate you control enters, draw a card.

Eerie Interlude

Exile any number of target creatures you control. Return those cards to the battlefield under their owner's control at the beginning of the next end step.

Black Dragon Gate

Black Dragon Gate enters tapped.
As Black Dragon Gate enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

Folk Hero

Commander creatures you own have "Whenever you cast a spell that shares a creature type with this creature, draw a card. This ability triggers only once each turn."

Sol Ring

Hardy Outlander

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, another target creature you control gets +X/+X until end of turn, where X is this creature's power."

Lantern Scout

Rally — Whenever Lantern Scout or another Ally you control enters, creatures you control gain lifelink until end of turn.

Arcane Signet

Azorius Guildgate

Azorius Guildgate enters tapped.
{T}: Add {W} or {U}.

Circuitous Route

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

Tavern Brawler

Commander creatures you own have "At the beginning of your upkeep, exile the top card of your library. This creature gets +X/+0 until end of turn, where X is that card's mana value. You may play that card this turn."

Cliffgate

Cliffgate enters tapped.
As Cliffgate enters, choose a color other than red.
{T}: Add {R} or one mana of the chosen color.

Open the Gates

Search your library for a basic land card or Gate card, reveal it, put it into your hand, then shuffle.

Loyal Unicorn

Vigilance
Lieutenant — At the beginning of combat on your turn, if you control your commander, prevent all combat damage that would be dealt to creatures you control this turn. Other creatures you control gain vigilance until end of turn.

Noble Heritage

Commander creatures you own have "When this creature enters and at the beginning of your upkeep, each player may put two +1/+1 counters on a creature they control. For each opponent who does, you gain protection from that player until your next turn." (You can't be targeted, dealt damage, or enchanted by anything controlled by that player.)

Selesnya Guildgate

Selesnya Guildgate enters tapped.
{T}: Add {G} or {W}.

Oran-Rief Survivalist

Whenever Oran-Rief Survivalist or another Ally you control enters, you may put a +1/+1 counter on Oran-Rief Survivalist.

Have

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Gruul Guildgate

Gruul Guildgate enters tapped.
{T}: Add {R} or {G}.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Simic Guildgate

Simic Guildgate enters tapped.
{T}: Add {G} or {U}.

Chromatic Lantern

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

Murasa Pyromancer

Whenever Murasa Pyromancer or another Ally you control enters, you may have Murasa Pyromancer deal damage to target creature equal to the number of Allies you control.

Thunderfoot Baloth

Trample
Lieutenant — As long as you control your commander, Thunderfoot Baloth gets +2/+2 and other creatures you control get +2/+2 and have trample.

Citadel Gate

Citadel Gate enters tapped.
As Citadel Gate enters, choose a color other than white.
{T}: Add {W} or one mana of the chosen color.

Kindred Dominance

Choose a creature type. Destroy all creatures that aren't of the chosen type.

Loyal Drake

Flying
Lieutenant — At the beginning of combat on your turn, if you control your commander, draw a card.

Turntimber Ranger

Whenever Turntimber Ranger or another Ally you control enters, you may create a 2/2 green Wolf creature token. If you do, put a +1/+1 counter on Turntimber Ranger.

Munda, Ambush Leader

Haste
Rally — Whenever Munda, Ambush Leader or another Ally you control enters, you may look at the top four cards of your library. If you do, reveal any number of Ally cards from among them, then put those cards on top of your library in any order and the rest on the bottom in any order.

Resolute Blademaster

Rally — Whenever Resolute Blademaster or another Ally you control enters, creatures you control gain double strike until end of turn.

Kalastria Healer

Rally — Whenever Kalastria Healer or another Ally you control enters, each opponent loses 1 life and you gain 1 life.

Agent of the Shadow Thieves

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, put a +1/+1 counter on this creature. It gains deathtouch and indestructible until end of turn."

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.

Seascape Aerialist

Whenever Seascape Aerialist or another Ally you control enters, you may have Ally creatures you control gain flying until end of turn.

Hero of Goma Fada

Rally — Whenever Hero of Goma Fada or another Ally you control enters, creatures you control gain indestructible until end of turn.

Boros Guildgate

Boros Guildgate enters tapped.
{T}: Add {R} or {W}.

Gond Gate

Gates you control enter untapped.
{T}: Add {C}.
{T}: Add one mana of any color that a Gate you control could produce.

Mountain

Loyal Apprentice

Haste
Lieutenant — At the beginning of combat on your turn, if you control your commander, create a 1/1 colorless Thopter artifact creature token with flying. That token gains haste until end of turn.

General Tazri

When General Tazri enters, you may search your library for an Ally creature card, reveal it, put it into your hand, then shuffle.
{W}{U}{B}{R}{G}: Ally creatures you control get +X/+X until end of turn, where X is the number of colors among those creatures.

Talus Paladin

Whenever Talus Paladin or another Ally you control enters, you may have Allies you control gain lifelink until end of turn, and you may put a +1/+1 counter on Talus Paladin.

Forest

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Gates Ablaze

Gates Ablaze deals X damage to each creature, where X is the number of Gates you control.

Nahiri's Resolve

Creatures you control get +1/+0 and have haste.
At the beginning of your end step, exile any number of nontoken artifacts and/or creatures you control. Return those cards to the battlefield under their owner's control at the beginning of your next upkeep.

Raised by Giants

Commander creatures you own have base power and toughness 10/10 and are Giants in addition to their other types.

Highland Berserker

Whenever Highland Berserker or another Ally you control enters, you may have Ally creatures you control gain first strike until end of turn.

Golgari Guildgate

Golgari Guildgate enters tapped.
{T}: Add {B} or {G}.

Ghostly Flicker

Exile two target artifacts, creatures, and/or lands you control, then return those cards to the battlefield under your control.

Swamp

Stormsurge Kraken

Hexproof
Lieutenant — As long as you control your commander, Stormsurge Kraken gets +2/+2 and has "Whenever Stormsurge Kraken becomes blocked, you may draw two cards."

Angelic Field Marshal

Flying
Lieutenant — As long as you control your commander, Angelic Field Marshal gets +2/+2 and creatures you control have vigilance.

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.

Island

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.

Agadeem Occultist

{T}: Put target creature card from an opponent's graveyard onto the battlefield under your control if its mana value is less than or equal to the number of Allies you control.

Dimir Guildgate

Dimir Guildgate enters tapped.
{T}: Add {U} or {B}.

Sea Gate

Sea Gate enters tapped.
As Sea Gate enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Plains

Far Traveler

Commander creatures you own have "At the beginning of your end step, exile up to one target tapped creature you control, then return it to the battlefield under its owner's control."

Rakdos Guildgate

Rakdos Guildgate enters tapped.
{T}: Add {B} or {R}.

The Black Gate

As The Black Gate enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}.
{1}{B}, {T}: Choose a player with the most life or tied for most life. Target creature can't be blocked by creatures that player controls this turn.

Loyal Guardian

Trample
Lieutenant — At the beginning of combat on your turn, if you control your commander, put a +1/+1 counter on each creature you control.

Vantress Visions

Copy target activated or triggered ability you control. You may choose new targets for the copy.

Virtue of Knowledge

If a permanent entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Virtue of Knowledge // Vantress Visions

Flaming Fist

Commander creatures you own have "Whenever this creature attacks, it gains double strike until end of turn."

Izzet Guildgate

Izzet Guildgate enters tapped.
{T}: Add {U} or {R}.

Plaza of Harmony

When Plaza of Harmony enters, if you control two or more Gates, you gain 3 life.
{T}: Add {C}.
{T}: Add one mana of any type that a Gate you control could produce.

Skyhunter Strike Force

Flying
Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
Lieutenant — As long as you control your commander, other creatures you control have melee.

Explore the Underdark

Search your library for up to two basic land cards and/or Gate cards, put them onto the battlefield tapped, then shuffle.
You take the initiative.

Cancel

Navigation Orb

{2}, {T}, Sacrifice Navigation Orb: Search your library for up to two basic land cards and/or Gate cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Loyal Subordinate

Menace (This creature can't be blocked except by two or more creatures.)
Lieutenant — At the beginning of combat on your turn, if you control your commander, each opponent loses 3 life.

Maskwood Nexus

Creatures you control are every creature type. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 2/2 blue Shapeshifter creature token with changeling. (It is every creature type.)

Demon of Wailing Agonies

Flying
Lieutenant — As long as you control your commander, Demon of Wailing Agonies gets +2/+2 and has "Whenever Demon of Wailing Agonies deals combat damage to a player, that player sacrifices a creature."

Harabaz Druid

{T}: Add X mana of any one color, where X is the number of Allies you control.

Tyrant's Familiar

Flying, haste
Lieutenant — As long as you control your commander, Tyrant's Familiar gets +2/+2 and has "Whenever Tyrant's Familiar attacks, it deals 7 damage to target creature defending player controls."

Counterspell

Veteran Soldier

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, for each opponent, create a 1/1 white Soldier creature token that's tapped and attacking that opponent."

Replicate

Create a token that's a copy of target creature you control.

Repudiate

Counter target activated or triggered ability. (Mana abilities can't be targeted.)