Arcane Signet

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

Cryptoplasm

At the beginning of your upkeep, you may have this creature become a copy of another target creature, except it has this ability.

Ruby Medallion

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

Firbolg Flutist

Enthralling Performance — When this creature enters, gain control of target creature you don't control until end of turn. Untap it. It gains haste and myriad until end of turn. (Whenever it attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Vesuvan Shapeshifter

As this creature enters or is turned face up, you may choose another creature on the battlefield. If you do, until this creature is turned face down, it becomes a copy of that creature, except it has "At the beginning of your upkeep, you may turn this creature face down."
Morph {1}{U}

Hivis of the Scale

You may choose not to untap Hivis during your untap step.
{T}: Gain control of target Dragon for as long as you control Hivis and Hivis remains tapped.

Counterspell

Sakashima's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Target opponent chooses a creature they control. You gain control of it.
• Choose a creature you control. Each other creature you control becomes a copy of that creature until end of turn.

Mirror Box

The "legend rule" doesn't apply to permanents you control.
Each legendary creature you control gets +1/+1.
Each nontoken creature you control gets +1/+1 for each other creature you control with the same name as that creature.

Island

Reliquary Tower

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

Kediss, Emberclaw Familiar

Whenever a commander you control deals combat damage to an opponent, it deals that much damage to each other opponent.
Partner (You can have two commanders if both have partner.)

Exotic Orchard

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

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.)

Faceless One

If Faceless One is your commander, choose a color before the game begins. Faceless One is the chosen color.
Choose a Background (You can have a Background as a second commander.)

Gigantoplasm

You may have this creature enter as a copy of any creature on the battlefield, except it has "{X}: This creature has base power and toughness X/X."

Command Tower

Mimic Vat

Imprint — Whenever a nontoken creature dies, you may exile that card. If you do, return each other card exiled with this artifact to its owner's graveyard.
{3}, {T}: Create a token that's a copy of a card exiled with this artifact. It gains haste. Exile it at the beginning of the next end step.

Hideous Taskmaster

Devoid (This card has no color.)
When you cast this spell, for each opponent, gain control of up to one target creature that player controls until end of turn. Untap those creatures. They gain trample, haste, and annihilator 1 until end of turn.
Trample, haste, annihilator 1 (Whenever this creature attacks, defending player sacrifices a permanent of their choice.)

Resculpt

Exile target artifact or creature. Its controller creates a 4/4 blue and red Elemental creature token.

Undercover Operative

You may have this creature enter 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.)

Keldon Overseer

Kicker {3}{R} (You may pay an additional {3}{R} as you cast this spell.)
Haste
When this creature enters, if it was kicked, gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.

Negate

Fellwar Stone

Rapid Hybridization

Destroy target creature. It can't be regenerated. That creature's controller creates a 3/3 green Frog Lizard creature token.

Big Score

As an additional cost to cast this spell, discard a card.
Draw two cards and create two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")

Pongify

Destroy target creature. It can't be regenerated. Its controller creates a 3/3 green Ape creature token.

Sol Ring

Elminster's Simulacrum

For each opponent, you create a token that's a copy of up to one target creature that player controls.

Copy Enchantment

You may have this enchantment enter as a copy of any enchantment on the battlefield.

Jeering Instigator

Morph {2}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When this creature is turned face up, if it's your turn, gain control of another target creature until end of turn. Untap that creature. It gains haste until end of turn.

Nascent Metamorph

Whenever this creature attacks or blocks, target opponent reveals cards from the top of their library until they reveal a creature card. This creature becomes a copy of that card until end of turn. Then that player puts all cards revealed this way on the bottom of their library in a random order.

Aladdin

{1}{R}{R}, {T}: Gain control of target artifact for as long as you control this creature.

Evolving Wilds

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

Myriad Landscape

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

Rogue's Passage

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

Thespian's Stage

{T}: Add {C}.
{2}, {T}: This land becomes a copy of target land, except it has this ability.

Coercive Recruiter

Whenever this creature or another Pirate you control enters, gain control of target creature until end of turn. Untap that creature. Until end of turn, it gains haste and becomes a Pirate in addition to its other types.

Chaos Warp

The owner of target permanent shuffles it into their library, then reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Kiki-Jiki, Mirror Breaker

Haste
{T}: Create a token that's a copy of target nonlegendary creature you control, except it has haste. Sacrifice it at the beginning of the next end step.

Mirrorpool

This land enters tapped.
{T}: Add {C}.
{2}{C}, {T}, Sacrifice this land: Copy target instant or sorcery spell you control. You may choose new targets for the copy.
{4}{C}, {T}, Sacrifice this land: Create a token that's a copy of target creature you control.

Unexpected Windfall

Mocking Doppelganger

Flash
You may have this creature enter 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.)

Memnarch

{1}{U}{U}: Target permanent becomes an artifact in addition to its other types. (This effect lasts indefinitely.)
{3}{U}: Gain control of target artifact. (This effect lasts indefinitely.)

Stunt Double

Flash
You may have this creature enter as a copy of any creature on the battlefield.

Chef's Kiss

Gain control of target spell that targets only a single permanent or player. Copy it, then reselect the targets at random for the spell and the copy. The new targets can't be you or a permanent you control.

Mirage Mirror

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

Body Double

You may have this creature enter as a copy of any creature card in a graveyard.

Dack Fayden

+1: Target player draws two cards, then discards two cards.
−2: Gain control of target artifact.
−6: You get an emblem with "Whenever you cast a spell that targets one or more permanents, gain control of those permanents."

Clone Legion

For each creature target player controls, create a token that's a copy of that creature.

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Agent of Treachery

When this creature enters, gain control of target permanent.
At the beginning of your end step, if you control three or more permanents you don't own, draw three cards.

Sword Coast Sailor

Commander creatures you own have "Whenever this creature attacks a player, if no opponent has more life than that player, this creature can't be blocked this turn."

Sapphire Medallion

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

Mirrormade

You may have this enchantment enter as a copy of any artifact or enchantment on the battlefield.

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.)

Mountain

Identity Thief

Whenever this creature attacks, you may exile another target nontoken creature. If you do, this creature becomes a copy of that creature until end of turn. Return the exiled card to the battlefield under its owner's control at the beginning of the next end step.

Sculpting Steel

You may have this artifact enter as a copy of any artifact on the battlefield.

Propaganda

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

Dominus of Fealty

Flying
At the beginning of your upkeep, you may gain control of target permanent until end of turn. If you do, untap it and it gains haste until end of turn.

Blatant Thievery

For each opponent, gain control of target permanent that player controls.

Captivating Crew

{3}{R}: Gain control of target creature an opponent controls until end of turn. Untap that creature. It gains haste until end of turn. Activate only as a sorcery.

Clever Impersonator

You may have this creature enter as a copy of any nonland permanent on the battlefield.

Stolen Identity

Create a token that's a copy of target artifact or creature.
Cipher (Then you may exile this spell card encoded on a creature you control. Whenever that creature deals combat damage to a player, its controller may cast a copy of the encoded card without paying its mana cost.)

Clone

You may have this creature enter as a copy of any creature on the battlefield.

Mercurial Pretender

You may have this creature enter as a copy of a creature you control, except it has "{2}{U}{U}: Return this creature to its owner's hand."

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.)

Frantic Search

Draw two cards, then discard two cards. Untap up to three lands.

Terramorphic Expanse

Irenicus's Vile Duplication

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

Shameless Charlatan

Commander creatures you own have "{2}{U}: This creature becomes a copy of another target creature."

Thrill of Possibility

As an additional cost to cast this spell, discard a card.
Draw two cards.

Copycrook

You may have this creature enter as a copy of any creature on the battlefield, except it has "Whenever this creature attacks, it connives." (Draw a card, then discard a card. If you discarded a nonland card, put a +1/+1 counter on this creature.)

Brainstorm

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

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.)

Zealous Conscripts

Haste
When this creature enters, gain control of target permanent until end of turn. Untap that permanent. It gains haste until end of turn.

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.

Vesuva

You may have this land enter tapped as a copy of any land on the battlefield.

An Offer You Can't Refuse

Counter target noncreature spell. Its controller creates two Treasure tokens. (They're artifacts with "{T}, Sacrifice this token: Add one mana of any color.")