Undercover Operative

You may have Undercover Operative enter the battlefield as a copy of any creature on the battlefield, except it enters with a shield counter on it if you control that creature. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)

Lord of Change

Flying, ward {3}
Architect of Deception — When Lord of Change enters the battlefield, draw three cards.

Mocking Doppelganger

Flash
You may have Mocking Doppelganger enter the battlefield as a copy of a creature an opponent controls, except it has "Other creatures with the same name as this creature are goaded." (They attack each combat if able and attack a player other than you if able.)

Castle Vantress

Castle Vantress enters the battlefield tapped unless you control an Island.
{T}: Add {U}.
{2}{U}{U}, {T}: Scry 2.

Maeve, Insidious Singer

{2}{U}: Goad target creature. Whenever that creature attacks one of your opponents this turn, you draw a card. (A goaded creature attacks each combat if able and attacks a player other than you if able, until your next turn.)

Aetherize

Return all attacking creatures to their owner's hand.

Nezahal, Primal Tide

This spell can't be countered.
You have no maximum hand size.
Whenever an opponent casts a noncreature spell, draw a card.
Discard three cards: Exile Nezahal, Primal Tide. Return it to the battlefield tapped under its owner's control at the beginning of the next end step.

Arcane Signet

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

Vedalken Orrery

You may cast spells as though they had flash.

Wayfarer's Bauble

{2}, {T}, Sacrifice Wayfarer's Bauble: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Island

Extraplanar Lens

Imprint — When Extraplanar Lens enters the battlefield, you may exile target land you control.
Whenever a land with the same name as the exiled card is tapped for mana, its controller adds one mana of any type that land produced.

Caged Sun

As Caged Sun enters the battlefield, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Sphinx of Enlightenment

Flying
When Sphinx of Enlightenment enters the battlefield, target opponent draws a card and you draw three cards.

Riptide Laboratory

{T}: Add {C}.
{1}{U}, {T}: Return target Wizard you control to its owner's hand.

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.

Propaganda

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

Artisan of Kozilek

When you cast this spell, you may return target creature card from your graveyard to the battlefield.
Annihilator 2 (Whenever this creature attacks, defending player sacrifices two permanents.)

Arcanis the Omnipotent

{T}: Draw three cards.
{2}{U}{U}: Return Arcanis the Omnipotent to its owner's hand.

Vodalian Illusionist

{U}{U}, {T}: Target creature phases out. (While it's phased out, it's treated as though it doesn't exist. It phases in before its controller untaps during their next untap step.)

Strionic Resonator

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

Everflowing Chalice

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.)
Everflowing Chalice enters the battlefield with a charge counter on it for each time it was kicked.
{T}: Add {C} for each charge counter on Everflowing Chalice.

Lonely Sandbar

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

Rite of Replication

Kicker {5} (You may pay an additional {5} as you cast this spell.)
Create a token that's a copy of target creature. If this spell was kicked, create five of those tokens instead.

Aetherplasm

Whenever Aetherplasm blocks a creature, you may return Aetherplasm to its owner's hand. If you do, you may put a creature card from your hand onto the battlefield blocking that creature.

Thran Dynamo

Dreamstone Hedron

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

Counterspell

Leyline of Anticipation

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield.
You may cast spells as though they had flash.

Fatespinner

At the beginning of each opponent's upkeep, that player chooses draw step, main phase, or combat phase. The player skips each instance of the chosen step or phase this turn.

Spark Double

You may have Spark Double enter the battlefield as a copy of a creature or planeswalker you control, except it enters with an additional +1/+1 counter on it if it's a creature, it enters with an additional loyalty counter on it if it's a planeswalker, and it isn't legendary.

Vanishing

Enchant creature
{U}{U}: Enchanted creature phases out. (While it's phased out, it's treated as though it doesn't exist. It phases in before its controller untaps during their next untap step.)

Aeon Engine

Aeon Engine enters the battlefield tapped.
{T}, Exile Aeon Engine: Reverse the game's turn order. (For example, if play had proceeded clockwise around the table, it now goes counterclockwise.)

Thran Temporal Gateway

{4}, {T}: You may put a historic permanent card from your hand onto the battlefield. (Artifacts, legendaries, and Sagas are historic.)

Sphinx of Magosi

Flying
{2}{U}: Draw a card, then put a +1/+1 counter on Sphinx of Magosi.

Omniscience

You may cast spells from your hand without paying their mana costs.

Sol Ring

Duplicant

Imprint — When Duplicant enters the battlefield, you may exile target nontoken creature.
As long as a card exiled with Duplicant is a creature card, Duplicant has the power, toughness, and creature types of the last creature card exiled with Duplicant. It's still a Shapeshifter.

Curse of the Swine

Exile X target creatures. For each creature exiled this way, its controller creates a 2/2 green Boar creature token.

Ixidron

As Ixidron enters the battlefield, turn all other nontoken creatures face down. (They're 2/2 creatures.)
Ixidron's power and toughness are each equal to the number of face-down creatures on the battlefield.

Engulf the Shore

Return to their owners' hands all creatures with toughness less than or equal to the number of Islands you control.

Kami of the Crescent Moon

At the beginning of each player's draw step, that player draws an additional card.

Braids, Conjurer Adept

At the beginning of each player's upkeep, that player may put an artifact, creature, or land card from their hand onto the battlefield.

Teferi, Mage of Zhalfir

Flash
Creature cards you own that aren't on the battlefield have flash.
Each opponent can cast spells only any time they could cast a sorcery.

Thought Vessel

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

Sower of Temptation

Flying
When Sower of Temptation enters the battlefield, gain control of target creature for as long as Sower of Temptation remains on the battlefield.

Mystic Confluence

Choose three. You may choose the same mode more than once.
• Counter target spell unless its controller pays {3}.
• Return target creature to its owner's hand.
• Draw a card.

Cackling Counterpart

Create a token that's a copy of target creature you control.
Flashback {5}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile 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.

Scourge of Fleets

When Scourge of Fleets enters the battlefield, return each creature your opponents control with toughness X or less to its owner's hand, where X is the number of Islands you control.

Hullbreaker Horror

Flash
This spell can't be countered.
Whenever you cast a spell, choose up to one —
• Return target spell you don't control to its owner's hand.
• Return target nonland permanent to its owner's hand.

Fellwar Stone

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

Reliquary Tower

Portal of Sanctuary

{1}, {T}: Return target creature you control and each Aura attached to it to their owners' hands. Activate only during your turn.

Kederekt Leviathan

When Kederekt Leviathan enters the battlefield, return all other nonland permanents to their owners' hands.
Unearth {6}{U} ({6}{U}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Stormtide Leviathan

Islandwalk (This creature can't be blocked as long as defending player controls an Island.)
All lands are Islands in addition to their other types.
Creatures without flying or islandwalk can't attack.

Seal of Removal

Sacrifice Seal of Removal: Return target creature to its owner's hand.

Rogue's Passage

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

Negate

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Windreader Sphinx

Flying
Whenever a creature with flying attacks, you may draw a card.

Commandeer

You may exile two blue cards from your hand rather than pay this spell's mana cost.
Gain control of target noncreature spell. You may choose new targets for it. (If that spell is an artifact, enchantment, or planeswalker, the permanent enters the battlefield under your control.)

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Quicksilver Amulet

{4}, {T}: You may put a creature card from your hand onto the battlefield.

Crystal Shard

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

Clever Impersonator

You may have Clever Impersonator enter the battlefield as a copy of any nonland permanent on the battlefield.

Aetherspouts

For each attacking creature, its owner puts it on the top or bottom of their library.

Mirage Mirror

{2}: Mirage Mirror becomes a copy of target artifact, creature, enchantment, or land until end of turn.

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.)

Cloudstone Curio

Whenever a nonartifact permanent enters the battlefield under your control, you may return another permanent you control that shares a permanent type with it to its owner's hand.