Consider

Surveil 1. (Look at the top card of your library. You may put it into your graveyard.)
Draw a card.

Dawnbringer Cleric

When this creature enters, choose one —
• Cure Wounds — You gain 2 life.
• Dispel Magic — Destroy target enchantment.
• Gentle Repose — Exile target card from a graveyard.

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.)

Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Draw a card.

Slip On the Ring

Exile target creature you own, then return it to the battlefield under your control. The Ring tempts you.

Skybridge Towers

This land enters tapped.
{T}: Add {W} or {U}.
{2}{W}{U}, {T}, Sacrifice this land: Draw a card.

Sol Ring

Soulherder

Whenever a creature is exiled from the battlefield, put a +1/+1 counter on this creature.
At the beginning of your end step, you may exile another target creature you control, then return that card to the battlefield under its owner's control.

Tune the Narrative

Draw a card. You get {E}{E} (two energy counters).

Wall of Omens

Defender
When this creature enters, draw a card.

Cloudblazer

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

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Turn to Mist

Exile target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Razorgrass Field

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {W}.

Razorgrass Ambush

Razorgrass Ambush deals 3 damage to target attacking or blocking creature.

Razorgrass Ambush // Razorgrass Field

Fade Away

For each creature, its controller sacrifices a permanent of their choice unless they pay {1}.

Angel of Finality

Flying
When this creature enters, exile target player's graveyard.

Inspiring Overseer

Flying
When this creature enters, you gain 1 life and draw a card.

Archaeomancer

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

Spirited Companion

Wispmare

Flying
When this creature enters, destroy target enchantment.
Evoke {W} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Don't Have

Slaughter the Strong

Each player chooses any number of creatures they control with total power 4 or less, then sacrifices all other creatures they control.

Command Tower

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

Distinguished Conjurer

Whenever another creature you control enters, you gain 1 life.
{4}{W}, {T}: Exile another target creature you control, then return it to the battlefield under its owner's control.

Vesperlark

Flying
When this creature leaves the battlefield, return target creature card with power 1 or less from your graveyard to the battlefield.
Evoke {1}{W} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Candlekeep Sage

Commander creatures you own have "When this creature enters or leaves the battlefield, draw a card."

Ephemerate

Exile target creature you control, then return it to the battlefield under its owner's control.
Rebound (If you cast this spell from your hand, exile it as it resolves. At the beginning of your next upkeep, you may cast this card from exile without paying its mana cost.)

Proxy

Counterspell

Have

Oji, the Exquisite Blade

When Oji enters, you gain 2 life and scry 2.
Whenever you cast your second spell each turn, exile up to one target creature you control, then return it to the battlefield under its owner's control.

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Peregrine Drake

Flying
When this creature enters, untap up to five lands.

Reconnaissance

{0}: Remove target attacking creature you control from combat and untap it. (If you activate during end of combat, the creature will untap after it deals combat damage.)

Serum Visionary

When this creature enters, draw a card, then scry 2.

Kor Cartographer

When this creature enters, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Negate

Ghostly Flicker

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

Secluded Steppe

This land enters tapped.
{T}: Add {W}.
Cycling {W} ({W}, Discard this card: Draw a card.)

Helpful Hunter

Island

Plains

Winter Eladrin

Gust of Wind — When this creature enters, return up to one other target creature to its owner's hand.

Hydroelectric Laboratory

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {U}.

Hydroelectric Specimen

Flash
When this creature enters, you may change the target of target instant or sorcery spell with a single target to this creature.

Hydroelectric Specimen // Hydroelectric Laboratory

Scrollshift

Exile up to one target artifact, creature, or enchantment you control, then return it to the battlefield under its owner's control.
Draw a card.

Reality Shift

Exile target creature. Its controller manifests the top card of their library. (That player puts the top card of their library onto the battlefield face down as a 2/2 creature. If it's a creature card, it can be turned face up any time for its mana cost.)

Cloudshift

Exile target creature you control, then return that card to the battlefield under your control.

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Witch-Blessed Meadow

Witch Enchanter

When this creature enters, destroy target artifact or enchantment an opponent controls.

Witch Enchanter // Witch-Blessed Meadow

Swords to Plowshares

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

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.

Aether Adept

When this creature enters, return target creature to its owner's hand.

Azorius Guildgate

This land enters tapped.
{T}: Add {W} or {U}.

Meteor Golem

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

Man-o'-War

Scampering Surveyor

When this creature enters, search your library for a basic land card or Cave card, put it onto the battlefield tapped, then shuffle.

Tranquil Cove

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {W} or {U}.

Displace

Exile up to two target creatures you control, then return those cards to the battlefield under their owner's control.

Arcane Signet

Blur

Exile target creature you control, then return that card to the battlefield under its owner's control.
Draw a card.

Azorius Chancery

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Filter Out

Return all noncreature, nonland permanents to their owners' hands.

Elite Guardmage

Flying
When this creature enters, you gain 3 life and draw a card.

Razortide Bridge

This land enters tapped.
Indestructible
{T}: Add {W} or {U}.

Talisman of Progress

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

Momentary Blink

Exile target creature you control, then return it to the battlefield under its owner's control.
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Obsessive Search

Draw a card.
Madness {U} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Orderly Plaza

Suppression Ray

Tap all creatures target player controls. You may pay any amount of {E}. If you do, choose up to that many creatures tapped this way. Put a stun counter on each of them. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Suppression Ray // Orderly Plaza

Capsize

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Return target permanent to its owner's hand.

Floodgate

Defender
When this creature has flying, sacrifice it.
When this creature leaves the battlefield, it deals damage to each nonblue creature without flying equal to half the number of Islands you control, rounded down.

Rescue the Foal

Exile target creature you control, then return that card to the battlefield under its owner's control. (Then exile this card. You may cast the creature later from exile.)

Pegasus Guardian

Flying
At the beginning of your end step, if a permanent you controlled left the battlefield this turn, create a 1/1 white Pegasus creature token with flying.

Pegasus Guardian // Rescue the Foal

Crystal Shard

{3}, {T} or {U}, {T}: Return target creature to its owner's hand unless its controller pays {1}.

Mystic Sanctuary

({T}: Add {U}.)
This land enters tapped unless you control three or more other Islands.
When this land enters untapped, you may put target instant or sorcery card from your graveyard on top of your library.

Nevermaker

Flying
When this creature leaves the battlefield, put target nonland permanent on top of its owner's library.
Evoke {3}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Echoing Truth

Return target nonland permanent and all other permanents with the same name as that permanent to their owners' hands.

Reliquary Tower

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

Fellwar Stone

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

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.