Boss's Chauffeur

Boss's Chauffeur enters with a number of +1/+1 counters on it equal to one plus the number of other creatures you control.
Alliance — Whenever another creature you control enters, put a +1/+1 counter on Boss's Chauffeur.
When Boss's Chauffeur dies, create a 1/1 green and white Citizen creature token for each +1/+1 counter on it.

Semester's End

Exile any number of target creatures and/or planeswalkers you control. At the beginning of the next end step, return each of them to the battlefield under its owner's control. Each of them enters with an additional +1/+1 counter on it if it's a creature and an additional loyalty counter on it if it's a planeswalker.

Panharmonicon

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

Llanowar Elves

Exotic Orchard

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

Insurrection

Untap all creatures and gain control of them until end of turn. They gain haste until end of turn.

Martyr's Cause

Sacrifice a creature: The next time a source of your choice would deal damage to any target this turn, prevent that damage.

Eternal Witness

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

Rockfall Vale

Rockfall Vale enters tapped unless you control two or more other lands.
{T}: Add {R} or {G}.

Impact Tremors

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

Farewell

Choose one or more —
• Exile all artifacts.
• Exile all creatures.
• Exile all enchantments.
• Exile all graveyards.

Hour of Revelation

This spell costs {3} less to cast if there are ten or more nonland permanents on the battlefield.
Destroy all nonland permanents.

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.

Stroke of Midnight

Destroy target nonland permanent. Its controller creates a 1/1 white Human creature token.

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.

Karmic Guide

Flying, protection from black
Echo {3}{W}{W} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When Karmic Guide enters, return target creature card from your graveyard to the battlefield.

Spectator Seating

Spectator Seating enters tapped unless you have two or more opponents.
{T}: Add {R} or {W}.

Soul Warden

Whenever another creature enters, you gain 1 life.

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.

Moon-Blessed Cleric

Divine Intervention — When Moon-Blessed Cleric enters, you may search your library for an enchantment card, reveal it, then shuffle and put that card on top.

Mistveil Plains

({T}: Add {W}.)
Mistveil Plains enters tapped.
{W}, {T}: Put target card from your graveyard on the bottom of your library. Activate only if you control two or more white permanents.

Sunpetal Grove

Sunpetal Grove enters tapped unless you control a Forest or a Plains.
{T}: Add {G} or {W}.

Yoshimaru, Ever Faithful

Whenever another legendary permanent you control enters, put a +1/+1 counter on Yoshimaru, Ever Faithful.
Partner (You can have two commanders if both have partner.)

Masked Vandal

Changeling (This card is every creature type.)
When Masked Vandal enters, you may exile a creature card from your graveyard. If you do, exile target artifact or enchantment an opponent controls.

Suture Priest

Whenever another creature you control enters, you may gain 1 life.
Whenever a creature an opponent controls enters, you may have that player lose 1 life.

Soul of the Harvest

Trample
Whenever another nontoken creature you control enters, you may draw a card.

Saltskitter

Whenever another creature enters, exile Saltskitter. Return Saltskitter to the battlefield under its owner's control at the beginning of the next end step.

Ashaya, Soul of the Wild

Ashaya, Soul of the Wild's power and toughness are each equal to the number of lands you control.
Nontoken creatures you control are Forest lands in addition to their other types. (They're still affected by summoning sickness.)

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.

Pull from Eternity

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

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Evolving Wilds

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Fanatical Devotion

Sacrifice a creature: Regenerate target creature.

Cabaretti Courtyard

When Cabaretti Courtyard enters, sacrifice it. When you do, search your library for a basic Mountain, Forest, or Plains card, put it onto the battlefield tapped, then shuffle and you gain 1 life.

Sanctum of Eternity

{T}: Add {C}.
{2}, {T}: Return target commander you own from the battlefield to your hand. Activate only during your turn.

Fyndhorn Elves

Omnath, Locus of Rage

Landfall — Whenever a land you control enters, create a 5/5 red and green Elemental creature token.
Whenever Omnath, Locus of Rage or another Elemental you control dies, Omnath deals 3 damage to any target.

Warstorm Surge

Whenever a creature you control enters, it deals damage equal to its power to any target.

Thorn Mammoth

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

Command Tower

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

Caustic Caterpillar

{1}{G}, Sacrifice Caustic Caterpillar: Destroy target artifact or enchantment.

Cinder Glade

({T}: Add {R} or {G}.)
Cinder Glade enters tapped unless you control two or more basic lands.

Rootbound Crag

Rootbound Crag enters tapped unless you control a Mountain or a Forest.
{T}: Add {R} or {G}.

Aid from the Cowl

Revolt — At the beginning of your end step, if a permanent you controlled left the battlefield this turn, reveal the top card of your library. If it's a permanent card, you may put it onto the battlefield. Otherwise, you may put it on the bottom of your library.

Avenger of Zendikar

When Avenger of Zendikar enters, create a 0/1 green Plant creature token for each land you control.
Landfall — Whenever a land you control enters, you may put a +1/+1 counter on each Plant creature you control.

Skyclave Apparition

When Skyclave Apparition enters, exile up to one target nonland, nontoken permanent you don't control with mana value 4 or less.
When Skyclave Apparition leaves the battlefield, the exiled card's owner creates an X/X blue Illusion creature token, where X is the mana value of the exiled card.

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.

Plains

Canopy Vista

({T}: Add {G} or {W}.)
Canopy Vista enters tapped unless you control two or more basic lands.

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.

Brushland

{T}: Add {C}.
{T}: Add {G} or {W}. Brushland deals 1 damage to you.

Aura Shards

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

Generous Gift

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

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.

Reclamation Sage

When Reclamation Sage enters, you may destroy target artifact or enchantment.

Riftsweeper

When Riftsweeper enters, choose target face-up exiled card. Its owner shuffles it into their library.

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.

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.

Champion of the Parish

Whenever another Human enters under your control, put a +1/+1 counter on Champion of the Parish.

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.

Clifftop Retreat

Clifftop Retreat enters tapped unless you control a Mountain or a Plains.
{T}: Add {R} or {W}.

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.

Soul's Attendant

Whenever another creature enters, you may gain 1 life.

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.

Jungle Shrine

Jungle Shrine enters tapped.
{T}: Add {R}, {G}, or {W}.

Forest

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.)

Haywire Mite

When Haywire Mite dies, you gain 2 life.
{G}, Sacrifice Haywire Mite: Exile target noncreature artifact or noncreature enchantment.

Beast Within

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

Hall of Heliod's Generosity

{T}: Add {C}.
{1}{W}, {T}: Put target enchantment card from your graveyard on top of your library.

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.

Temple of Triumph

Temple of Triumph enters tapped.
When Temple of Triumph enters, scry 1.
{T}: Add {R} or {W}.

Karplusan Forest

{T}: Add {C}.
{T}: Add {R} or {G}. Karplusan Forest deals 1 damage to you.

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.

Essence Warden

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.

Witty Roastmaster

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

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.

Loran of the Third Path

Vigilance
When Loran of the Third Path enters, destroy up to one target artifact or enchantment.
{T}: You and target opponent each draw a card.

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.

Tibalt's Trickery

Counter target spell. Choose 1, 2, or 3 at random. Its controller mills that many cards, then exiles cards from the top of their library until they exile a nonland card with a different name than that spell. They may cast that card without paying its mana cost. Then they put the exiled cards on the bottom of their library in a random order.

Radiant Solar

Flying, lifelink
Whenever Radiant Solar or another nontoken creature you control enters, venture into the dungeon. (Enter the first room or advance to the next room.)
{W}, Discard Radiant Solar: Venture into the dungeon and you gain 3 life.

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.

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.

Mountain

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.

Lapse of Certainty

Counter target spell. If that spell is countered this way, put it on top of its owner's library instead of into that player's graveyard.