Watcher for Tomorrow

Hideaway 4 (When this creature enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Watcher for Tomorrow enters the battlefield tapped.
When Watcher for Tomorrow leaves the battlefield, put the exiled card into its owner's hand.

Mycosynth Wellspring

When Mycosynth Wellspring enters the battlefield or is put into a graveyard from the battlefield, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Phyrexian Rebirth

Destroy all creatures, then create an X/X colorless Phyrexian Horror artifact creature token, where X is the number of creatures destroyed this way.

Planar Outburst

Destroy all nonland creatures.
Awaken 4—{5}{W}{W}{W} (If you cast this spell for {5}{W}{W}{W}, also put four +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)

Act of Authority

When Act of Authority enters the battlefield, you may exile target artifact or enchantment.
At the beginning of your upkeep, you may exile target artifact or enchantment. If you do, its controller gains control of Act of Authority.

Phyrexian Ingester

Imprint — When Phyrexian Ingester enters the battlefield, you may exile target nontoken creature.
Phyrexian Ingester gets +X/+Y, where X is the exiled creature card's power and Y is its toughness.

Sailor of Means

When Sailor of Means enters the battlefield, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Cloudshift

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

Cloudblazer

Flying
When Cloudblazer enters the battlefield, you gain 2 life and draw two cards.

Deadeye Harpooner

Revolt — When Deadeye Harpooner enters the battlefield, if a permanent you controlled left the battlefield this turn, destroy target tapped creature an opponent controls.

Soulherder

Whenever a creature is exiled from the battlefield, put a +1/+1 counter on Soulherder.
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.

Secluded Steppe

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

Oblivion Ring

When Oblivion Ring enters the battlefield, exile another target nonland permanent.
When Oblivion Ring leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Brago, King Eternal

Flying
Whenever Brago, King Eternal deals combat damage to a player, exile any number of target nonland permanents you control, then return those cards to the battlefield under their owner's control.

Desert of the Mindful

Desert of the Mindful enters the battlefield tapped.
{T}: Add {U}.
Cycling {1}{U} ({1}{U}, Discard this card: Draw a card.)

Sunblast Angel

Flying
When Sunblast Angel enters the battlefield, destroy all tapped creatures.

End Hostilities

Destroy all creatures and all permanents attached to creatures.

Luminate Primordial

Vigilance
When Luminate Primordial enters the battlefield, for each opponent, exile up to one target creature that player controls and that player gains life equal to its power.

Terramorphic Expanse

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

Displace

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

Sea Gate Oracle

When Sea Gate Oracle enters the battlefield, look at the top two cards of your library. Put one of them into your hand and the other on the bottom of your library.

Elite Guardmage

Flying
When Elite Guardmage enters the battlefield, you gain 3 life and draw a card.

Vessel of Endless Rest

When Vessel of Endless Rest enters the battlefield, put target card from a graveyard on the bottom of its owner's library.
{T}: Add one mana of any color.

Unwind

Counter target noncreature spell. Untap up to three lands.

Ichor Wellspring

When Ichor Wellspring enters the battlefield or is put into a graveyard from the battlefield, draw a card.

Mana Geode

When Mana Geode enters the battlefield, scry 1.
{T}: Add one mana of any color.

Essence Flux

Exile target creature you control, then return that card to the battlefield under its owner's control. If it's a Spirit, put a +1/+1 counter on it.

Temple of the False God

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

Kor Cartographer

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

Seashell Cameo

Ur-Golem's Eye

Mistmeadow Witch

{2}{W}{U}: Exile target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Call for Unity

Revolt — At the beginning of your end step, if a permanent you controlled left the battlefield this turn, put a unity counter on Call for Unity.
Creatures you control get +1/+1 for each unity counter on Call for Unity.

Eldrazi Skyspawner

Devoid (This card has no color.)
Flying
When Eldrazi Skyspawner enters the battlefield, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add {C}."

Teferi's Time Twist

Exile target permanent you control. Return that card to the battlefield under its owner's control at the beginning of the next end step. If it enters the battlefield as a creature, it enters with an additional +1/+1 counter on it.

Hierophant's Chalice

When Hierophant's Chalice enters the battlefield, target opponent loses 1 life and you gain 1 life.
{T}: Add {C}.

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.

Darksteel Ingot

Indestructible (Effects that say "destroy" don't destroy this artifact.)
{T}: Add one mana of any color.

Azorius Chancery

Azorius Chancery enters the battlefield tapped.
When Azorius Chancery enters the battlefield, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Consulate Surveillance

When Consulate Surveillance enters the battlefield, you get {E}{E}{E}{E} (four energy counters).
Pay {E}{E}: Prevent all damage that would be dealt to you this turn by a source of your choice.

Trial of Knowledge

When Trial of Knowledge enters the battlefield, draw three cards, then discard a card.
When a Cartouche enters the battlefield under your control, return Trial of Knowledge to its owner's hand.

Stalking Leonin

When Stalking Leonin enters the battlefield, secretly choose an opponent.
Reveal the player you chose: Exile target creature that's attacking you if it's controlled by the chosen player. Activate only once.

Meteor Golem

When Meteor Golem enters the battlefield, destroy target nonland permanent an opponent controls.

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.)

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice Hedron Archive: Draw two cards.

Spine of Ish Sah

When Spine of Ish Sah enters the battlefield, destroy target permanent.
When Spine of Ish Sah is put into a graveyard from the battlefield, return Spine of Ish Sah to its owner's hand.

Acrobatic Maneuver

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

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Reflector Mage

When Reflector Mage enters the battlefield, 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.

Calciform Pools

{T}: Add {C}.
{1}, {T}: Put a storage counter on Calciform Pools.
{1}, Remove X storage counters from Calciform Pools: Add X mana in any combination of {W} and/or {U}.

Island

Desert of the True

Desert of the True enters the battlefield tapped.
{T}: Add {W}.
Cycling {1}{W} ({1}{W}, Discard this card: Draw a card.)

Dovin's Acuity

When Dovin's Acuity enters the battlefield, you gain 2 life and draw a card.
Whenever you cast an instant spell during your main phase, you may return Dovin's Acuity to its owner's hand.

Myr Battlesphere

When Myr Battlesphere enters the battlefield, create four 1/1 colorless Myr artifact creature tokens.
Whenever Myr Battlesphere attacks, you may tap X untapped Myr you control. If you do, Myr Battlesphere gets +X/+0 until end of turn and deals X damage to the player or planeswalker it's attacking.

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Unquestioned Authority

Enchant creature
When Unquestioned Authority enters the battlefield, draw a card.
Enchanted creature has protection from creatures.

Plains

Fiend Hunter

When Fiend Hunter enters the battlefield, you may exile another target creature.
When Fiend Hunter leaves the battlefield, return the exiled card to the battlefield under its owner's control.

Diluvian Primordial

Flying
When Diluvian Primordial enters the battlefield, for each opponent, you may cast up to one target instant or sorcery card from that player's graveyard without paying its mana cost. If a spell cast this way would be put into a graveyard, exile it instead.

Traveler's Cloak

Enchant creature
As Traveler's Cloak enters the battlefield, choose a land type.
When Traveler's Cloak enters the battlefield, draw a card.
Enchanted creature has landwalk of the chosen type. (It can't be blocked as long as defending player controls a land of that type.)

Master Splicer

When Master Splicer enters the battlefield, create a 3/3 colorless Phyrexian Golem artifact creature token.
Golems you control get +1/+1.

Wing Splicer

When Wing Splicer enters the battlefield, create a 3/3 colorless Phyrexian Golem artifact creature token.
Golem creatures you control have flying.

Halimar Depths

Halimar Depths enters the battlefield tapped.
When Halimar Depths enters the battlefield, look at the top three cards of your library, then put them back in any order.
{T}: Add {U}.

Whirler Rogue

When Whirler Rogue enters the battlefield, create two 1/1 colorless Thopter artifact creature tokens with flying.
Tap two untapped artifacts you control: Target creature can't be blocked this turn.

Aqueous Form

Enchant creature
Enchanted creature can't be blocked.
Whenever enchanted creature attacks, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.)

Evolving Wilds

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

Angel of Serenity

Flying
When Angel of Serenity enters the battlefield, you may exile up to three other target creatures from the battlefield and/or creature cards from graveyards.
When Angel of Serenity leaves the battlefield, return the exiled cards to their owners' hands.

Consulate Crackdown

When Consulate Crackdown enters the battlefield, exile all artifacts your opponents control until Consulate Crackdown leaves the battlefield.

Prophetic Prism

When Prophetic Prism enters the battlefield, draw a card.
{1}, {T}: Add one mana of any color.

Dreamstone Hedron

{T}: Add {C}{C}{C}.
{3}, {T}, Sacrifice Dreamstone Hedron: Draw three cards.

Rewind

Counter target spell. Untap up to four lands.

Stoic Rebuttal

Metalcraft — This spell costs {1} less to cast if you control three or more artifacts.
Counter target spell.

Reality Acid

Enchant permanent
Vanishing 3 (This Aura enters the battlefield with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When Reality Acid leaves the battlefield, enchanted permanent's controller sacrifices it.

Sphinx of Uthuun

Flying
When Sphinx of Uthuun enters the battlefield, reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Induced Amnesia

When Induced Amnesia enters the battlefield, target player exiles all cards from their hand face down, then draws that many cards.
When Induced Amnesia is put into a graveyard from the battlefield, return the exiled cards to their owner's hand.

Pentarch Ward

Enchant creature
As Pentarch Ward enters the battlefield, choose a color.
When Pentarch Ward enters the battlefield, draw a card.
Enchanted creature has protection from the chosen color. This effect doesn't remove Pentarch Ward.

Spectra Ward

Enchant creature
Enchanted creature gets +2/+2 and has protection from all colors. This effect doesn't remove Auras. (It can't be blocked, targeted, or dealt damage by anything that's white, blue, black, red, or green.)

Lonely Sandbar

Lonely Sandbar enters the battlefield tapped.
{T}: Add {U}.
Cycling {U} ({U}, Discard this card: Draw a card.)