The War Doctor

Whenever one or more other permanents phase out and whenever one or more other cards are put into exile from anywhere, put a time counter on The War Doctor.
Whenever The War Doctor attacks, it deals damage equal to the number of time counters on it to any target. If a creature dealt damage this way would die this turn, exile it instead.

Open the Way

X can't be greater than the number of players in the game.
Reveal cards from the top of your library until you reveal X land cards. Put those land cards onto the battlefield tapped and the rest on the bottom of your library in a random order.

Mentor of the Meek

Whenever another creature you control with power 2 or less enters, you may pay {1}. If you do, draw a card.

Lignify

Enchant creature
Enchanted creature is a Treefolk with base power and toughness 0/4 and loses all abilities.

Sun Titan

Vigilance
Whenever Sun Titan enters or attacks, you may return target permanent card with mana value 3 or less from your graveyard to the battlefield.

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, 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.

Flaming Fist Officer

Whenever another creature you control leaves the battlefield, put a +1/+1 counter on Flaming Fist Officer.

Ninth Bridge Patrol

Whenever another creature you control leaves the battlefield, put a +1/+1 counter on Ninth Bridge Patrol.

Wyrm's Crossing Patrol

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Honor-Worn Shaku

{T}: Add {C}.
Tap an untapped legendary permanent you control: Untap Honor-Worn Shaku.

Winds of Abandon

Exile target creature you don't control. For each creature exiled this way, its controller searches their library for a basic land card. Those players put those cards onto the battlefield tapped, then shuffle.
Overload {4}{W}{W} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Soul Warden

Whenever another creature enters, you gain 1 life.

Heronblade Elite

Vigilance
Whenever another Human you control enters, put a +1/+1 counter on Heronblade Elite.
{T}: Add X mana of any one color, where X is Heronblade Elite's power.

Kenrith's Transformation

Enchant creature
When Kenrith's Transformation enters, draw a card.
Enchanted creature loses all abilities and is a green Elk creature with base power and toughness 3/3. (It loses all other card types and creature types.)

Gimli of the Glittering Caves

Double strike
Whenever another legendary creature you control enters, put a +1/+1 counter on Gimli of the Glittering Caves.
Whenever Gimli deals combat damage to a player, create a Treasure token.

Plains

Mountain

Annie Flash, the Veteran

Flash
When Annie Flash, the Veteran enters, if you cast it, return target permanent card with mana value 3 or less from your graveyard to the battlefield tapped.
Whenever Annie Flash becomes tapped, exile the top two cards of your library. You may play those cards this turn.

Gandalf the White

Flash
You may cast legendary spells and artifact spells as though they had flash.
If a legendary permanent or an artifact entering or leaving the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Nature's Lore

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

Purphoros, God of the Forge

Indestructible
As long as your devotion to red is less than five, Purphoros isn't a creature.
Whenever another creature you control enters, Purphoros deals 2 damage to each opponent.
{2}{R}: Creatures you control get +1/+0 until end of turn.

Panharmonicon

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

Grasp of Fate

When Grasp of Fate enters, for each opponent, exile up to one target nonland permanent that player controls until Grasp of Fate leaves the battlefield. (Those permanents return under their owners' control.)

Thorn Mammoth

Trample
Whenever Thorn Mammoth or another creature you control enters, Thorn Mammoth fights up to one target creature you don't control.

Welcoming Vampire

Flying
Whenever one or more other creatures you control with power 2 or less enter, draw a card. This ability triggers only once each turn.

Rocco, Cabaretti Caterer

When Rocco, Cabaretti Caterer enters, if you cast it, you may search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.

Impact Tremors

Whenever a creature you control enters, Impact Tremors deals 1 damage to each opponent.

Legolas Greenleaf

Reach
Legolas Greenleaf can't be blocked by creatures with power 2 or less.
Whenever another legendary creature you control enters, put a +1/+1 counter on Legolas Greenleaf.
Whenever Legolas Greenleaf deals combat damage to a player, draw a card.

Norin the Wary

When a player casts a spell or a creature attacks, exile Norin the Wary. Return it to the battlefield under its owner's control at the beginning of the next end step.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Arcane Signet

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

Loyal Retainers

Sacrifice Loyal Retainers: Return target legendary creature card from your graveyard to the battlefield. Activate only during your turn, before attackers are declared.

Aura Shards

Whenever a creature you control enters, you may destroy target artifact or enchantment.

Gala Greeters

Alliance — Whenever another creature you control enters, choose one that hasn't been chosen this turn —
• Put a +1/+1 counter on Gala Greeters.
• Create a tapped Treasure token.
• You gain 2 life.

Sol Ring

Swords to Plowshares

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

Battle Angels of Tyr

Flying, myriad
Whenever Battle Angels of Tyr deals combat damage to a player, draw a card if that player has more cards in hand than each other player. Then you create a Treasure token if that player controls more lands than each other player. Then you gain 3 life if that player has more life than each other player.

Tocasia's Welcome

Whenever one or more creatures you control with mana value 3 or less enter, draw a card. This ability triggers only once each turn.

Extraction Specialist

Lifelink
When Extraction Specialist enters, return target creature card with mana value 2 or less from your graveyard to the battlefield. That creature can't attack or block for as long as you control Extraction Specialist.

Champion of Lambholt

Creatures with power less than Champion of Lambholt's power can't block creatures you control.
Whenever another creature you control enters, put a +1/+1 counter on Champion of Lambholt.

Essence Warden

Eternal Witness

When Eternal Witness enters, you may return target card from your graveyard to your hand.

Samwise Gamgee

Whenever another nontoken creature you control enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Sacrifice three Foods: Return target historic card from your graveyard to your hand. (Artifacts, legendaries, and Sagas are historic.)

Hammers of Moradin

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)
Whenever Hammers of Moradin attacks, for each opponent, tap up to one target creature that player controls.

Pull from Eternity

Put target face-up exiled card into its owner's graveyard.

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Mace of the Valiant

Equipped creature gets +1/+1 for each charge counter on Mace of the Valiant and has vigilance.
Whenever a creature you control enters, put a charge counter on Mace of the Valiant.
Equip {3}

Outpost Siege

As Outpost Siege enters, choose Khans or Dragons.
• Khans — At the beginning of your upkeep, exile the top card of your library. Until end of turn, you may play that card.
• Dragons — Whenever a creature you control leaves the battlefield, Outpost Siege deals 1 damage to any target.

Genesis Chamber

Whenever a nontoken creature enters, if Genesis Chamber is untapped, that creature's controller creates a 1/1 colorless Myr artifact creature token.

Luminous Phantom

Flying
Whenever another creature you control leaves the battlefield, you gain 1 life.
If Luminous Phantom would be put into a graveyard from anywhere, exile it instead.

Lunarch Veteran

Whenever another creature you control enters, you gain 1 life.
Disturb {1}{W} (You may cast this card from your graveyard transformed for its disturb cost.)

Lunarch Veteran // Luminous Phantom

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Prosperous Innkeeper

When Prosperous Innkeeper enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")
Whenever another creature you control enters, you gain 1 life.

Beast Within

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Forest

Park Bleater

Whenever another creature you own enters, you get {TK}.
{W}, {T}: You may put a sticker on a creature you own that entered this turn.

Rose Room Treasurer

Alliance — Whenever another creature you control enters, create a Treasure token if this is the first or second time this ability has resolved this turn. Otherwise, you may pay {X}. When you do, Rose Room Treasurer deals X damage to any target.

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

Confusion in the Ranks

Whenever an artifact, creature, or enchantment enters, its controller chooses target permanent another player controls that shares a card type with it. Exchange control of those permanents.

Rumor Gatherer

Alliance — Whenever another creature you control enters, scry 1. If this is the second time this ability has resolved this turn, draw a card instead.

Witty Roastmaster

Alliance — Whenever another creature you control enters, Witty Roastmaster deals 1 damage to each opponent.

Elesh Norn, Mother of Machines

Vigilance
If a permanent entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
Permanents entering don't cause abilities of permanents your opponents control to trigger.

Helping Hand

Return target creature card with mana value 3 or less from your graveyard to the battlefield tapped.

Warleader's Call

Creatures you control get +1/+1.
Whenever a creature you control enters, Warleader's Call deals 1 damage to each opponent.

Blessed Sanctuary

Prevent all noncombat damage that would be dealt to you and creatures you control.
Whenever a nontoken creature you control enters, create a 2/2 white Unicorn creature token.

Vigilante Justice

Whenever a Human you control enters, Vigilante Justice deals 1 damage to any target.

Guardian Project

Whenever a nontoken creature you control enters, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.