Xantcha, Sleeper Agent

Xantcha, Sleeper Agent enters the battlefield under the control of an opponent of your choice.
Xantcha attacks each combat if able and can't attack its owner or planeswalkers its owner controls.
{3}: Xantcha's controller loses 2 life and you draw a card. Any player may activate this ability.

Disrupt Decorum

Goad all creatures you don't control. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

Curse of Opulence

Enchant player
Whenever enchanted player is attacked, create a Gold token. Each opponent attacking that player does the same. (A Gold token is an artifact with "Sacrifice this artifact: Add one mana of any color.")

Land Tax

At the beginning of your upkeep, if an opponent controls more lands than you, you may search your library for up to three basic land cards, reveal them, put them into your hand, then shuffle.

Master of Ceremonies

At the beginning of your upkeep, each opponent chooses money, friends, or secrets. For each player who chose money, you and that player each create a Treasure token. For each player who chose friends, you and that player each create a 1/1 green and white Citizen creature token. For each player who chose secrets, you and that player each draw a card.

Kardur, Doomscourge

When Kardur, Doomscourge enters the battlefield, until your next turn, creatures your opponents control attack each combat if able and attack a player other than you if able.
Whenever an attacking creature dies, each opponent loses 1 life and you gain 1 life.

Scrubland

Swords to Plowshares

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

Arcane Signet

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

Smothering Tithe

Whenever an opponent draws a card, that player may pay {2}. If the player doesn't, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Court of Ambition

When Court of Ambition enters the battlefield, you become the monarch.
At the beginning of your upkeep, each opponent loses 3 life unless they discard a card. If you're the monarch, instead each opponent loses 6 life unless they discard two cards.

Temple of Silence

Temple of Silence enters the battlefield tapped.
When Temple of Silence enters the battlefield, scry 1.
{T}: Add {W} or {B}.

Throne Warden

At the beginning of your end step, if you're the monarch, put a +1/+1 counter on Throne Warden.

Crackling Doom

Crackling Doom deals 2 damage to each opponent. Each opponent sacrifices a creature with the greatest power among creatures that player controls.

Loran of the Third Path

Vigilance
When Loran of the Third Path enters the battlefield, destroy up to one target artifact or enchantment.
{T}: You and target opponent each draw a card.

Secret Rendezvous

You and target opponent each draw three cards.

Demonic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Idyllic Tutor

Search your library for an enchantment card, reveal it, put it into your hand, then shuffle.

Royal Assassin

Swamp

Marchesa's Decree

When Marchesa's Decree enters the battlefield, you become the monarch.
Whenever a creature attacks you or a planeswalker you control, that creature's controller loses 1 life.

Council's Judgment

Will of the council — Starting with you, each player votes for a nonland permanent you don't control. Exile each permanent with the most votes or tied for most votes.

Garrulous Sycophant

At the beginning of your end step, if you're the monarch, each opponent loses 1 life and you gain 1 life.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.

Command Tower

Bojuka Bog

Bojuka Bog enters the battlefield tapped.
When Bojuka Bog enters the battlefield, exile target player's graveyard.
{T}: Add {B}.

Tempting Contract

At the beginning of your upkeep, each opponent may create a Treasure token. For each opponent who does, you create a Treasure token.

Court of Grace

When Court of Grace enters the battlefield, you become the monarch.
At the beginning of your upkeep, create a 1/1 white Spirit creature token with flying. If you're the monarch, create a 4/4 white Angel creature token with flying instead.

Mountain

Temple of Triumph

Temple of Triumph enters the battlefield tapped.
When Temple of Triumph enters the battlefield, scry 1.
{T}: Add {R} or {W}.

Plateau

Inkshield

Prevent all combat damage that would be dealt to you this turn. For each 1 damage prevented this way, create a 2/1 white and black Inkling creature token with flying.

Vault of Champions

Vault of Champions enters the battlefield tapped unless you have two or more opponents.
{T}: Add {W} or {B}.

Skyline Despot

Flying
When Skyline Despot enters the battlefield, you become the monarch.
At the beginning of your upkeep, if you're the monarch, create a 5/5 red Dragon creature token with flying.

Boros Charm

Choose one —
• Boros Charm deals 4 damage to target player or planeswalker.
• Permanents you control gain indestructible until end of turn.
• Target creature gains double strike until end of turn.

Read the Bones

Scry 2, then draw two cards. You lose 2 life.

Keeper of the Accord

At the beginning of each opponent's end step, if that player controls more creatures than you, create a 1/1 white Soldier creature token.
At the beginning of each opponent's end step, if that player controls more lands than you, you may search your library for a basic Plains card, put it onto the battlefield tapped, then shuffle.

Blind Obedience

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Artifacts and creatures your opponents control enter the battlefield tapped.

Knight of the White Orchid

First strike
When Knight of the White Orchid enters the battlefield, if an opponent controls more lands than you, you may search your library for a Plains card, put it onto the battlefield, then shuffle.

Sol Ring

Godless Shrine

({T}: Add {W} or {B}.)
As Godless Shrine enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Taunt from the Rampart

Goad all creatures your opponents control. Until your next turn, those creatures can't block. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

Phyrexian Vindicator

Flying
If damage would be dealt to Phyrexian Vindicator, prevent that damage. When damage is prevented this way, Phyrexian Vindicator deals that much damage to any other target.

Arid Mesa

{T}, Pay 1 life, Sacrifice Arid Mesa: Search your library for a Mountain or Plains card, put it onto the battlefield, then shuffle.

Archon of Coronation

Flying
When Archon of Coronation enters the battlefield, you become the monarch.
As long as you're the monarch, damage doesn't cause you to lose life. (When a creature deals combat damage to you, its controller still becomes the monarch.)

Duelist's Heritage

Whenever one or more creatures attack, you may have target attacking creature gain double strike until end of turn.

Ruinous Ultimatum

Destroy all nonland permanents your opponents control.

Elas il-Kor, Sadistic Pilgrim

Deathtouch
Whenever another creature enters the battlefield under your control, you gain 1 life.
Whenever another creature you control dies, each opponent loses 1 life.

Plains

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.

Flawless Maneuver

If you control a commander, you may cast this spell without paying its mana cost.
Creatures you control gain indestructible until end of turn.

Emberwilde Captain

When Emberwilde Captain enters the battlefield, you become the monarch.
Whenever an opponent attacks you while you're the monarch, Emberwilde Captain deals damage to that player equal to the number of cards in their hand.

Badlands

Cut a Deal

Each opponent draws a card, then you draw a card for each opponent who drew a card this way.

Wedding Ring

When Wedding Ring enters the battlefield, if it was cast, target opponent creates a token that's a copy of it.
Whenever an opponent who controls an artifact named Wedding Ring draws a card during their turn, you draw a card.
Whenever an opponent who controls an artifact named Wedding Ring gains life during their turn, you gain that much life.

Court of Embereth

When Court of Embereth enters the battlefield, you become the monarch.
At the beginning of your upkeep, create a 3/1 red Knight creature token. Then if you're the monarch, Court of Embereth deals X damage to each opponent, where X is the number of creatures you control.

Protector of the Crown

When Protector of the Crown enters the battlefield, you become the monarch.
All damage that would be dealt to you is dealt to Protector of the Crown instead.

Kambal, Consul of Allocation

Whenever an opponent casts a noncreature spell, that player loses 2 life and you gain 2 life.

Sheoldred, the Apocalypse

Deathtouch
Whenever you draw a card, you gain 2 life.
Whenever an opponent draws a card, they lose 2 life.

Reliquary Tower

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

Custodi Lich

When Custodi Lich enters the battlefield, you become the monarch.
Whenever you become the monarch, target player sacrifices a creature.

Lightning Greaves

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

Rakdos Signet

Knights of the Black Rose

When Knights of the Black Rose enters the battlefield, you become the monarch.
Whenever an opponent becomes the monarch, if you were the monarch as the turn began, that player loses 2 life and you gain 2 life.

Deflecting Palm

The next time a source of your choice would deal damage to you this turn, prevent that damage. If damage is prevented this way, Deflecting Palm deals that much damage to that source's controller.

Sundown Pass

Sundown Pass enters the battlefield tapped unless you control two or more other lands.
{T}: Add {R} or {W}.

Termination Facilitator

{T}: Put a bounty counter on target creature or planeswalker. Activate only as a sorcery.
Whenever a creature or planeswalker an opponent controls with a bounty counter on it is dealt damage, destroy it.

Mathas, Fiend Seeker

Menace
At the beginning of your end step, put a bounty counter on target creature an opponent controls. For as long as that creature has a bounty counter on it, it has "When this creature dies, each opponent draws a card and gains 2 life."

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Noble Heritage

Commander creatures you own have "When this creature enters the battlefield and at the beginning of your upkeep, each player may put two +1/+1 counters on a creature they control. For each opponent who does, you gain protection from that player until your next turn." (You can't be targeted, dealt damage, or enchanted by anything controlled by that player.)

Drana and Linvala

Flying, vigilance
Activated abilities of creatures your opponents control can't be activated.
Drana and Linvala has all activated abilities of all creatures your opponents control. You may spend mana as though it were mana of any color to activate those abilities.

Enlightened Tutor

Search your library for an artifact or enchantment card, reveal it, then shuffle and put that card on top.

Tenuous Truce

Enchant opponent
At the beginning of enchanted opponent's end step, you and that player each draw a card.
When you attack enchanted opponent or a planeswalker they control or when they attack you or a planeswalker you control, sacrifice Tenuous Truce.

Ghostly Prison

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

Sign in Blood

Target player draws two cards and loses 2 life.

Court of Ire

When Court of Ire enters the battlefield, you become the monarch.
At the beginning of your upkeep, Court of Ire deals 2 damage to any target. If you're the monarch, it deals 7 damage instead.

Queen Marchesa

Deathtouch, haste
When Queen Marchesa enters the battlefield, you become the monarch.
At the beginning of your upkeep, if an opponent is the monarch, create a 1/1 black Assassin creature token with deathtouch and haste.

Breena, the Demagogue

Flying
Whenever a player attacks one of your opponents, if that opponent has more life than another of your opponents, that attacking player draws a card and you put two +1/+1 counters on a creature you control.

Assemble the Legion

At the beginning of your upkeep, put a muster counter on Assemble the Legion. Then create a 1/1 red and white Soldier creature token with haste for each muster counter on Assemble the Legion.

Sacred Foundry

({T}: Add {R} or {W}.)
As Sacred Foundry enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Marsh Flats

{T}, Pay 1 life, Sacrifice Marsh Flats: Search your library for a Plains or Swamp card, put it onto the battlefield, then shuffle.

Urborg, Tomb of Yawgmoth

Each land is a Swamp in addition to its other land types.

Teysa, Envoy of Ghosts

Vigilance, protection from creatures
Whenever a creature deals combat damage to you, destroy that creature. Create a 1/1 white and black Spirit creature token with flying.

Norn's Annex

({W/P} can be paid with either {W} or 2 life.)
Creatures can't attack you or planeswalkers you control unless their controller pays {W/P} for each of those creatures.