Archaeomancer's Map

When Archaeomancer's Map enters, search your library for up to two basic Plains cards, reveal them, put them into your hand, then shuffle.
Whenever a land an opponent controls enters, if that player controls more lands than you, you may put a land card from your hand onto the battlefield.

Endless Atlas

{2}, {T}: Draw a card. Activate only if you control three or more lands with the same name.

Hedron Crawler

{T}: Add {C}. ({C} represents colorless mana.)

Loyal Sentry

When Loyal Sentry blocks a creature, destroy that creature and Loyal Sentry.

Monologue Tax

Whenever an opponent casts their second spell each turn, you create a Treasure token.

Valor in Akros

Whenever a creature you control enters, creatures you control get +1/+1 until end of turn.

Concerted Effort

At the beginning of each upkeep, creatures you control gain flying until end of turn if a creature you control has flying. The same is true for fear, first strike, double strike, landwalk, protection, trample, and vigilance.

Umbilicus

At the beginning of each player's upkeep, that player may pay 2 life. If they don't, they return a permanent they control to its owner's hand.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice this artifact: Draw two cards.

Binding Mummy

Whenever another Zombie you control enters, you may tap target artifact or creature.

Cartographer's Hawk

Flying
When Cartographer's Hawk deals combat damage to a player who controls more lands than you, return it to its owner's hand. If you do, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Venerated Loxodon

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
When Venerated Loxodon enters, put a +1/+1 counter on each creature that convoked it.

Eiganjo Free-Riders

Flying
At the beginning of your upkeep, return a white creature you control to its owner's hand.

Manakin

Unbreakable Formation

Creatures you control gain indestructible until end of turn.
Addendum — If you cast this spell during your main phase, put a +1/+1 counter on each of those creatures and they gain vigilance until end of turn.

Endless One

Endless One enters with X +1/+1 counters on it.

Signal Pest

Battle cry (Whenever this creature attacks, each other attacking creature gets +1/+0 until end of turn.)
Signal Pest can't be blocked except by creatures with flying or reach.

Benevolent Bodyguard

Sacrifice Benevolent Bodyguard: Target creature you control gains protection from the color of your choice until end of turn.

Scapegoat

As an additional cost to cast this spell, sacrifice a creature.
Return any number of target creatures you control to their owner's hand.

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.

Leonin Relic-Warder

When Leonin Relic-Warder enters, you may exile target artifact or enchantment.
When Leonin Relic-Warder leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Ornithopter

Oketra's Monument

White creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, create a 1/1 white Warrior creature token with vigilance.

Stonecloaker

Flash
Flying
When Stonecloaker enters, return a creature you control to its owner's hand.
When Stonecloaker enters, exile target card from a graveyard.

Selfless Spirit

Flying
Sacrifice Selfless Spirit: Creatures you control gain indestructible until end of turn.

Benalish Marshal

Palladium Myr

Jeskai Barricade

Flash (You may cast this spell any time you could cast an instant.)
Defender
When Jeskai Barricade enters, you may return another target creature you control to its owner's hand.

Thraben Inspector

When Thraben Inspector enters, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Shifting Wall

Defender (This creature can't attack.)
Shifting Wall enters with X +1/+1 counters on it.

Reverent Mantra

You may exile a white card from your hand rather than pay this spell's mana cost.
Choose a color. All creatures gain protection from the chosen color until end of turn.

Dauntless Bodyguard

As Dauntless Bodyguard enters, choose another creature you control.
Sacrifice Dauntless Bodyguard: The chosen creature gains indestructible until end of turn.

Wall of Omens

Defender
When Wall of Omens enters, draw a card.

Make a Stand

Creatures you control get +1/+0 and gain indestructible until end of turn. (Damage and effects that say "destroy" don't destroy them.)

Emeria Shepherd

Flying
Landfall — Whenever a land you control enters, you may return target nonland permanent card from your graveyard to your hand. If that land is a Plains, you may return that nonland permanent card to the battlefield instead.

Soul Warden

Whenever another creature enters, you gain 1 life.

Odric, Lunarch Marshal

At the beginning of each combat, creatures you control gain first strike until end of turn if a creature you control has first strike. The same is true for flying, deathtouch, double strike, haste, hexproof, indestructible, lifelink, menace, reach, skulk, trample, and vigilance.

Resolute Watchdog

Defender
{1}, Sacrifice Resolute Watchdog: Target creature you control gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

War Priest of Thune

When War Priest of Thune enters, you may destroy target enchantment.

Children of Korlis

Sacrifice Children of Korlis: You gain life equal to the life you've lost this turn. (Damage causes loss of life.)

Gold Myr

Rootborn Defenses

Populate. Creatures you control gain indestructible until end of turn. (To populate, create a token that's a copy of a creature token you control.)

Brought Back

Choose up to two target permanent cards in your graveyard that were put there from the battlefield this turn. Return them to the battlefield tapped.

Cathars' Crusade

Whenever a creature you control enters, put a +1/+1 counter on each creature you control.

Dust Elemental

Flash (You may cast this spell any time you could cast an instant.)
Flying; fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
When Dust Elemental enters, return three creatures you control to their owner's hand.

Kami of False Hope

Sacrifice Kami of False Hope: Prevent all combat damage that would be dealt this turn.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Bygone Bishop

Flying
Whenever you cast a creature spell with mana value 3 or less, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Alms Collector

Flash
If an opponent would draw two or more cards, instead you and that player each draw a card.

Pearl Medallion

White spells you cast cost {1} less to cast.

Akroma's Blessing

Choose a color. Creatures you control gain protection from the chosen color until end of turn.
Cycling {W} ({W}, Discard this card: Draw a card.)

Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice Mind Stone: Draw a card.

Whitemane Lion

Flash
When Whitemane Lion enters, return a creature you control to its owner's hand.

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.

Ghost Quarter

{T}: Add {C}.
{T}, Sacrifice Ghost Quarter: Destroy target land. Its controller may search their library for a basic land card, put it onto the battlefield, then shuffle.

Kor Skyfisher

Flying
When Kor Skyfisher enters, return a permanent you control to its owner's hand.

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Secret Rendezvous

You and target opponent each draw three cards.

Aviary Mechanic

When Aviary Mechanic enters, you may return another permanent you control to its owner's hand.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Secluded Steppe

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

Plains

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.

God-Eternal Oketra

Double strike
Whenever you cast a creature spell, create a 4/4 black Zombie Warrior creature token with vigilance.
When God-Eternal Oketra dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

Imposing Sovereign

Creatures your opponents control enter tapped.

Mardu Woe-Reaper

Whenever Mardu Woe-Reaper or another Warrior you control enters, you may exile target creature card from a graveyard. If you do, you gain 1 life.

Skyscanner

Flying
When Skyscanner enters, draw a card.

Ugin's Conjurant

Ugin's Conjurant enters with X +1/+1 counters on it.
If damage would be dealt to Ugin's Conjurant while it has a +1/+1 counter on it, prevent that damage and remove that many +1/+1 counters from Ugin's Conjurant.

Stormfront Riders

Flying
When Stormfront Riders enters, return two creatures you control to their owner's hand.
Whenever Stormfront Riders or another creature is returned to your hand from the battlefield, create a 1/1 white Soldier creature token.