Might Makes Right

At the beginning of combat on your turn, if you control each creature on the battlefield with the greatest power, gain control of target creature an opponent controls until end of turn. Untap that creature. It gains haste until end of turn. (It can attack and {T} this turn.)

Mountain

Treacherous Pit-Dweller

When this creature enters from a graveyard, target opponent gains control of it.
Undying (When this creature dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Harmless Offering

Target opponent gains control of target permanent you control.

Scrambleverse

For each nonland permanent, choose a player at random. Then each player gains control of each permanent for which they were chosen. Untap those permanents.

Prisoner's Dilemma

Each opponent secretly chooses silence or snitch, then the choices are revealed. If each opponent chose silence, Prisoner's Dilemma deals 4 damage to each of them. If each opponent chose snitch, Prisoner's Dilemma deals 8 damage to each of them. Otherwise, Prisoner's Dilemma deals 12 damage to each opponent who chose silence.
Flashback {5}{R}{R}

Curse of Hospitality

Enchant player
Creatures attacking enchanted player have trample.
Whenever a creature deals combat damage to enchanted player, that player exiles the top card of their library. Until end of turn, that creature's controller may play that card and they may spend mana as though it were mana of any color to cast that spell.

Enslaved Horror

When this creature enters, each other player may return a creature card from their graveyard to the battlefield.

Mages' Contest

You and target spell's controller bid life. You start the bidding with a bid of 1. In turn order, each player may top the high bid. The bidding ends if the high bid stands. The high bidder loses life equal to the high bid. If you win the bidding, counter that spell.

Ghoulish Impetus

Enchant creature
Enchanted creature gets +1/+1, has deathtouch, and is goaded.
When enchanted creature dies, return this card to the battlefield at the beginning of the next end step.

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.)

Plague of Vermin

Starting with you, each player may pay any amount of life. Repeat this process until no one pays life. Each player creates a 1/1 black Rat creature token for each 1 life they paid this way.

Sleeper Agent

When this creature enters, target opponent gains control of it.
At the beginning of your upkeep, this creature deals 2 damage to you.

Demonic Lore

When this enchantment enters, draw three cards.
At the beginning of your end step, you lose 2 life for each card in your hand.

Bronze Bombshell

When a player other than this creature's owner controls it, that player sacrifices it. If the player does, this creature deals 7 damage to the player.

Endless Whispers

Each creature has "When this creature dies, choose target opponent. That player puts this card from its owner's graveyard onto the battlefield under their control at the beginning of the next end step."

Mogg Infestation

Destroy all creatures target player controls. For each creature that died this way, that player creates two 1/1 red Goblin creature tokens.

Xantcha, Sleeper Agent

Xantcha enters 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.

Knowledge Pool

Imprint — When this artifact enters, each player exiles the top three cards of their library.
Whenever a player casts a spell from their hand, that player exiles it. If the player does, they may cast a spell from among other cards exiled with this artifact without paying its mana cost.

Game of Chaos

Flip a coin. If you win the flip, you gain 1 life and target opponent loses 1 life, and you decide whether to flip again. If you lose the flip, you lose 1 life and that opponent gains 1 life, and that player decides whether to flip again. Double the life stakes with each flip.

Archfiend of the Dross

Flying
This creature enters with four oil counters on it.
At the beginning of your upkeep, remove an oil counter from this creature. Then if it has no oil counters on it, you lose the game.
Whenever a creature an opponent controls dies, its controller loses 2 life.

Jinxed Idol

At the beginning of your upkeep, this artifact deals 2 damage to you.
Sacrifice a creature: Target opponent gains control of this artifact.

Descent of the Dragons

Destroy any number of target creatures. For each creature destroyed this way, its controller creates a 4/4 red Dragon creature token with flying.

Charmbreaker Devils

At the beginning of your upkeep, return an instant or sorcery card at random from your graveyard to your hand.
Whenever you cast an instant or sorcery spell, this creature gets +4/+0 until end of turn.

Opposition Agent

Flash
You control your opponents while they're searching their libraries.
While an opponent is searching their library, they exile each card they find. You may play those cards for as long as they remain exiled, and you may spend mana as though it were mana of any color to cast them.

Khârn the Betrayer

Berzerker — Khârn the Betrayer attacks or blocks each combat if able.
Sigil of Corruption — When you lose control of Khârn the Betrayer, draw two cards.
The Betrayer — If damage would be dealt to Khârn the Betrayer, prevent that damage and an opponent of your choice gains control of it.

Goblin Festival

{2}: This enchantment deals 1 damage to any target. Flip a coin. If you lose the flip, choose one of your opponents. That player gains control of this enchantment.

Last One Standing

Choose a creature at random, then destroy the rest.

Lightning Storm

Lightning Storm deals X damage to any target, where X is 3 plus the number of charge counters on Lightning Storm.
Discard a land card: Put two charge counters on Lightning Storm. You may choose a new target for it. Any player may activate this ability but only if Lightning Storm is on the stack.

Swamp

Custody Battle

Enchant creature
Enchanted creature has "At the beginning of your upkeep, target opponent gains control of this creature unless you sacrifice a land."

Fateful Handoff

Draw cards equal to the mana value of target artifact or creature you control. An opponent gains control of that permanent.

Starke of Rath

{T}: Destroy target artifact or creature. That permanent's controller gains control of Starke. (This effect lasts indefinitely.)

Goblin Cadets

Whenever this creature blocks or becomes blocked, target opponent gains control of it. (This removes this creature from combat.)

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 token: Add one mana of any color.")

Greed's Gambit

When this enchantment enters, you draw three cards, gain 6 life, and create three 2/1 black Bat creature tokens with flying.
At the beginning of your end step, you discard a card, lose 2 life, and sacrifice a creature.
When this enchantment leaves the battlefield, you discard three cards, lose 6 life, and sacrifice three creatures.

Measure of Wickedness

At the beginning of your end step, sacrifice this enchantment and you lose 8 life.
Whenever another card is put into your graveyard from anywhere, target opponent gains control of this enchantment.

Head Games

Target opponent puts the cards from their hand on top of their library. Search that player's library for that many cards. The player puts those cards into their hand, then shuffles.

Dragon Mage

Flying
Whenever this creature deals combat damage to a player, each player discards their hand, then draws seven cards.

Illicit Auction

Each player may bid life for control of target creature. You start the bidding with a bid of 0. In turn order, each player may top the high bid. The bidding ends if the high bid stands. The high bidder loses life equal to the high bid and gains control of the creature. (This effect lasts indefinitely.)

Jinxed Choker

At the beginning of your end step, target opponent gains control of this artifact and puts a charge counter on it.
At the beginning of your upkeep, this artifact deals damage to you equal to the number of charge counters on it.
{3}: Put a charge counter on this artifact or remove one from it.

Witch Engine

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
{T}: Add {B}{B}{B}{B}. Target opponent gains control of this creature. (Activate only as an instant.)

Incite

Target creature becomes red until end of turn and attacks this turn if able.

False Cure

Until end of turn, whenever a player gains life, that player loses 2 life for each 1 life they gained.

Humble Defector

{T}: Draw two cards. Target opponent gains control of this creature. Activate only during your turn.

Rainbow Vale

{T}: Add one mana of any color. An opponent gains control of this land at the beginning of the next end step.

Transmogrify

Exile target creature. That creature's controller reveals cards from the top of their library until they reveal a creature card. That player puts that card onto the battlefield, then shuffles the rest into their library.

Thieves' Auction

Exile all nontoken permanents. Starting with you, each player chooses one of the exiled cards and puts it onto the battlefield tapped under their control. Repeat this process until all cards exiled this way have been chosen.

Abyssal Persecutor

Flying, trample
You can't win the game and your opponents can't lose the game.

Phage the Untouchable

When Phage enters, if you didn't cast it from your hand, you lose the game.
Whenever Phage deals combat damage to a creature, destroy that creature. It can't be regenerated.
Whenever Phage deals combat damage to a player, that player loses the game.

Bazaar Trader

{T}: Target player gains control of target artifact, creature, or land you control.

Curse of Chaos

Enchant player
Whenever a player attacks enchanted player with one or more creatures, that attacking player may discard a card. If the player does, they draw a card.

Risky Move

At the beginning of each player's upkeep, that player gains control of this enchantment.
When you gain control of this enchantment from another player, choose a creature you control and an opponent. Flip a coin. If you lose the flip, that opponent gains control of that creature.

Transmogrifying Wand

This artifact enters with three charge counters on it.
{1}, {T}, Remove a charge counter from this artifact: Destroy target creature. Its controller creates a 2/4 white Ox creature token. Activate only as a sorcery.

Sol Ring

Demonic Pact

At the beginning of your upkeep, choose one that hasn't been chosen —
• This enchantment deals 4 damage to any target and you gain 4 life.
• Target opponent discards two cards.
• Draw two cards.
• You lose the game.

Shiny Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Command Tower

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

Boldwyr Heavyweights

Trample
When this creature enters, each opponent may search their library for a creature card and put it onto the battlefield. Then each player who searched their library this way shuffles.

Cauldron Dance

Cast this spell only during combat.
Return target creature card from your graveyard to the battlefield. That creature gains haste. Return it to your hand at the beginning of the next end step.
You may put a creature card from your hand onto the battlefield. That creature gains haste. Its controller sacrifices it at the beginning of the next end step.

Offer Immortality

Target creature gains deathtouch and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Dark Ritual

Ricochet

Whenever a player casts a spell that targets a single player, each player rolls a six-sided die. Change the target of that spell to the player with the lowest result. Reroll to break ties, if necessary.

Jinxed Ring

Whenever a nontoken permanent is put into your graveyard from the battlefield, this artifact deals 1 damage to you.
Sacrifice a creature: Target opponent gains control of this artifact. (This effect lasts indefinitely.)

Captive Audience

This enchantment enters under the control of an opponent of your choice.
At the beginning of your upkeep, choose one that hasn't been chosen —
• Your life total becomes 4.
• Discard your hand.
• Each opponent creates five 2/2 black Zombie creature tokens.

Curse of Bloodletting

Enchant player
If a source would deal damage to enchanted player, it deals double that damage to that player instead.

Phyrexian Negator

Trample
Whenever this creature is dealt damage, sacrifice that many permanents.

Hithlain Rope

This artifact can't be sacrificed.
{1}, {T}: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle. The player to your right gains control of this artifact.
{2}, {T}: Draw a card. The player to your right gains control of this artifact.

Steel Golem

Pain's Reward

Each player may bid life. You start the bidding with a bid of any number. In turn order, each player may top the high bid. The bidding ends if the high bid stands. The high bidder loses life equal to the high bid and draws four cards.

Hurl Through Hell

Exile target creature. Until the end of your next turn, you may cast that card and you may spend mana as though it were mana of any color to cast that spell.

Confusion in the Ranks

Whenever an artifact, creature, or enchantment enters, its controller chooses target permanent another player controls that shares a card type with it. Exchange control of those permanents.

Arcane Signet

Wildfire Devils

When this creature enters and at the beginning of your upkeep, choose a player at random. That player exiles an instant or sorcery card from their graveyard. Copy that card. You may cast the copy without paying its mana cost.

Insurrection

Untap all creatures and gain control of them until end of turn. They gain haste until end of turn.

Assault Suit

Equipped creature gets +2/+2, has haste, can't attack you or planeswalkers you control, and can't be sacrificed.
At the beginning of each opponent's upkeep, you may have that player gain control of equipped creature until end of turn. If you do, untap it.
Equip {3}

Wishclaw Talisman

This artifact enters with three wish counters on it.
{1}, {T}, Remove a wish counter from this artifact: Search your library for a card, put it into your hand, then shuffle. An opponent gains control of this artifact. Activate only during your turn.