Demonic Tutor

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

Plains

Vela the Night-Clad

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Other creatures you control have intimidate.
Whenever Vela or another creature you control leaves the battlefield, each opponent loses 1 life.

Hero's Downfall

Negate

Sea of Clouds

This land enters tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Swan Song

Counter target enchantment, instant, or sorcery spell. Its controller creates a 2/2 blue Bird creature token with flying.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Counterspell

Island

Drowned Catacomb

This land enters tapped unless you control an Island or a Swamp.
{T}: Add {U} or {B}.

Deadeye Navigator

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Deadeye Navigator is paired with another creature, each of those creatures has "{1}{U}: Exile this creature, then return it to the battlefield under your control."

The Chain Veil

At the beginning of your end step, if you didn't activate a loyalty ability of a planeswalker this turn, you lose 2 life.
{4}, {T}: For each planeswalker you control, you may activate one of its loyalty abilities once this turn as though none of its loyalty abilities have been activated this turn.

Cloudblazer

Flying
When this creature enters, you gain 2 life and draw two cards.

Oath of Teferi

When Oath of Teferi enters, exile another target permanent you control. Return it to the battlefield under its owner's control at the beginning of the next end step.
You may activate the loyalty abilities of planeswalkers you control twice each turn rather than only once.

Restoration Angel

Flash
Flying
When this creature enters, you may exile target non-Angel creature you control, then return that card to the battlefield under your control.

Morphic Pool

This land enters tapped unless you have two or more opponents.
{T}: Add {U} or {B}.

Dimir Signet

Sunken Hollow

({T}: Add {U} or {B}.)
This land enters tapped unless you control two or more basic lands.

Watery Grave

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

Felidar Guardian

When this creature enters, you may exile another target permanent you control, then return that card to the battlefield under its owner's control.

Underground River

{T}: Add {C}.
{T}: Add {U} or {B}. This land deals 1 damage to you.

Caves of Koilos

{T}: Add {C}.
{T}: Add {W} or {B}. This land deals 1 damage to you.

Hallowed Fountain

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

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Azorius Signet

Disallow

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

Mulldrifter

Flying
When this creature enters, draw two cards.
Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Command Tower

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

Baleful Strix

Flying, deathtouch
When this creature enters, 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.

Swamp

Panharmonicon

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

Prairie Stream

({T}: Add {W} or {U}.)
This land enters tapped unless you control two or more basic lands.

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. This land deals 1 damage to you.

Ravenous Chupacabra

When this creature enters, destroy target creature an opponent controls.

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Whir of Invention

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.)
Search your library for an artifact card with mana value X or less, put it onto the battlefield, then shuffle.

Archaeomancer

When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Swords to Plowshares

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

Godless Shrine

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

Fabricate

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

Day of Judgment

Debt to the Deathless

Each opponent loses two times X life. You gain life equal to the life lost this way.

Reflector Mage

When this creature enters, return target creature an opponent controls to its owner's hand. That creature's owner can't cast spells with the same name as that creature until your next turn.

Isolated Chapel

This land enters tapped unless you control a Plains or a Swamp.
{T}: Add {W} or {B}.

Torment of Hailfire

Repeat the following process X times. Each opponent loses 3 life unless that player sacrifices a nonland permanent of their choice or discards a card.

Glacial Fortress

This land enters tapped unless you control a Plains or an Island.
{T}: Add {W} or {U}.

Aminatou, the Fateshifter

+1: Draw a card, then put a card from your hand on top of your library.
−1: Exile another target permanent you own, then return it to the battlefield under your control.
−6: Choose left or right. Each player gains control of all nonland permanents other than Aminatou controlled by the next player in the chosen direction.
Aminatou, the Fateshifter can be your commander.