Have

Portent of Betrayal

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Claws of Gix

{1}, Sacrifice a permanent: You gain 1 life.

Mob Rule

Choose one —
• Gain control of all creatures with power 4 or greater until end of turn. Untap those creatures. They gain haste until end of turn.
• Gain control of all creatures with power 3 or less until end of turn. Untap those creatures. They gain haste until end of turn.

Aether Flash

Whenever a creature enters, Aether Flash deals 2 damage to it.

Dual Casting

Enchant creature
Enchanted creature has "{R}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy."

Cruel Entertainment

Choose target player and another target player. The first player controls the second player during the second player's next turn, and the second player controls the first player during the first player's next turn.

Magmatic Force

At the beginning of each upkeep, Magmatic Force deals 3 damage to any target.

Song-Mad Ruins

Song-Mad Ruins enters tapped.
{T}: Add {R}.

Song-Mad Treachery

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.

Song-Mad Treachery // Song-Mad Ruins

Vulturous Aven

Flying
Exploit (When this creature enters, you may sacrifice a creature.)
When Vulturous Aven exploits a creature, you draw two cards and you lose 2 life.

Dreamshaper Shaman

At the beginning of your end step, you may pay {2}{R} and sacrifice a nonland permanent. If you do, reveal cards from the top of your library until you reveal a nonland permanent card. Put that card onto the battlefield and the rest on the bottom of your library in a random order.

Bloodflow Connoisseur

Sacrifice a creature: Put a +1/+1 counter on Bloodflow Connoisseur.

Ghastly Conscription

Exile all creature cards from target player's graveyard in a face-down pile, shuffle that pile, then manifest those cards. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Vial Smasher the Fierce

Whenever you cast your first spell each turn, choose an opponent at random. Vial Smasher the Fierce deals damage equal to that spell's mana value to that player or a planeswalker that player controls.
Partner (You can have two commanders if both have partner.)

Galvanoth

At the beginning of your upkeep, you may look at the top card of your library. You may cast it without paying its mana cost if it's an instant or sorcery spell.

Harness by Force

Strive — This spell costs {2}{R} more to cast for each target beyond the first.
Gain control of any number of target creatures until end of turn. Untap those creatures. They gain haste until end of turn.

Unwilling Recruit

Gain control of target creature until end of turn. Untap that creature. It gets +X/+0 and gains haste until end of turn.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Traitorous Blood

Gain control of target creature until end of turn. Untap it. It gains trample and haste until end of turn.

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Mindslaver

{4}, {T}, Sacrifice Mindslaver: You control target player during that player's next turn. (You see all cards that player could see and make all decisions for the player.)

Reiterate

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Copy target instant or sorcery spell. You may choose new targets for the copy.

Gutless Ghoul

{1}, Sacrifice a creature: You gain 2 life.

Burnished Hart

{3}, Sacrifice this creature: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Metallic Mastery

Gain control of target artifact until end of turn. Untap that artifact. It gains haste until end of turn.

Rakdos Signet

Threaten

Untap target creature and gain control of it until end of turn. That creature gains haste until end of turn. (It can attack and {T} this turn.)

Rakdos Locket

{T}: Add {B} or {R}.
{B/R}{B/R}{B/R}{B/R}, {T}, Sacrifice Rakdos Locket: Draw two cards.

Sheoldred, Whispering One

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)
At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.
At the beginning of each opponent's upkeep, that player sacrifices a creature of their choice.

Scourge of the Skyclaves

Kicker {4}{B}
When you cast this spell, if it was kicked, each player loses half their life, rounded up.
Scourge of the Skyclaves's power and toughness are each equal to 20 minus the highest life total among players.

Olivia Voldaren

Flying
{1}{R}: Olivia Voldaren deals 1 damage to another target creature. That creature becomes a Vampire in addition to its other types. Put a +1/+1 counter on Olivia Voldaren.
{3}{B}{B}: Gain control of target Vampire for as long as you control Olivia Voldaren.

Fellwar Stone

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

Woe Strider

When Woe Strider enters, create a 0/1 white Goat creature token.
Sacrifice another creature: Scry 1.
Escape—{3}{B}{B}, Exile four other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)
Woe Strider escapes with two +1/+1 counters on it.

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.

Vicious Shadows

Whenever a creature dies, you may have Vicious Shadows deal damage to target player equal to the number of cards in that player's hand.

Cut?

Wild Ricochet

You may choose new targets for target instant or sorcery spell. Then copy that spell. You may choose new targets for the copy.

Tresserhorn Sinks

Tresserhorn Sinks enters tapped.
{T}: Add {B} or {R}.

Mask of Immolation

When Mask of Immolation enters, create a 1/1 red Elemental creature token, then attach Mask of Immolation to it.
Equipped creature has "Sacrifice this creature: It deals 1 damage to any target."
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Mountain

Furnace Celebration

Whenever you sacrifice another permanent, you may pay {2}. If you do, Furnace Celebration deals 2 damage to any target.

Harsh Mentor

Whenever an opponent activates an ability of an artifact, creature, or land on the battlefield, if it isn't a mana ability, Harsh Mentor deals 2 damage to that player.

Traitorous Instinct

Gain control of target creature until end of turn. Untap that creature. Until end of turn, it gets +2/+0 and gains haste.

Sign in Blood

Target player draws two cards and loses 2 life.

Gibbering Fiend

When Gibbering Fiend enters, it deals 1 damage to each opponent.
Delirium — At the beginning of each opponent's upkeep, if there are four or more card types among cards in your graveyard, Gibbering Fiend deals 1 damage to that player.

Snow-Covered Mountain

Pawn of Ulamog

Whenever Pawn of Ulamog or another nontoken creature you control dies, you may create a 0/1 colorless Eldrazi Spawn creature token. It has "Sacrifice this creature: Add {C}."

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, Charmbreaker Devils gets +4/+0 until end of turn.

Solemn Simulacrum

When this creature enters, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.
When this creature dies, you may draw a card.

Darksteel Ingot

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

Act of Treason

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. (It can attack and {T} this turn.)

Succumb to Temptation

Reassembling Skeleton

{1}{B}: Return this card from your graveyard to the battlefield tapped.

Snow-Covered Swamp

Limits of Solidarity

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Profane Insight

You draw a card and you lose 1 life. (Then exile this card. You may cast the creature later from exile.)

Foulmire Knight

Foulmire Knight // Profane Insight

Slaughter-Priest of Mogis

Whenever you sacrifice a permanent, Slaughter-Priest of Mogis gets +2/+0 until end of turn.
{2}, Sacrifice another creature or an enchantment: Slaughter-Priest of Mogis gains first strike until end of turn.

Rakdos Carnarium

Rakdos Carnarium enters tapped.
When Rakdos Carnarium enters, return a land you control to its owner's hand.
{T}: Add {B}{R}.

Anax, Hardened in the Forge

Anax's power is equal to your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)
Whenever Anax or another nontoken creature you control dies, create a 1/1 red Satyr creature token with "This creature can't block." If the creature had power 4 or greater, create two of those tokens instead.

Culling Dais

{T}, Sacrifice a creature: Put a charge counter on Culling Dais.
{1}, Sacrifice Culling Dais: Draw a card for each charge counter on Culling Dais.

Kari Zev's Expertise

Gain control of target creature or Vehicle until end of turn. Untap it. It gains haste until end of turn.
You may cast a spell with mana value 2 or less from your hand without paying its mana cost.

Rakdos Guildgate

This land enters tapped.
{T}: Add {B} or {R}.

Mass Mutiny

For each opponent, gain control of up to one target creature that player controls until end of turn. Untap those creatures. They gain haste until end of turn.

Erebos, God of the Dead

Indestructible
As long as your devotion to black is less than five, Erebos isn't a creature. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
Your opponents can't gain life.
{1}{B}, Pay 2 life: Draw a card.

Double Vision

Whenever you cast your first instant or sorcery spell each turn, copy that spell. You may choose new targets for the copy.

Hagra Broodpit

Hagra Broodpit enters tapped.
{T}: Add {B}.

Hagra Mauling

This spell costs {1} less to cast if an opponent controls no basic lands.
Destroy target creature.

Hagra Mauling // Hagra Broodpit

Swamp

Etali, Primal Storm

Whenever Etali attacks, exile the top card of each player's library, then you may cast any number of spells from among those cards without paying their mana costs.

Rocky Tar Pit

Rocky Tar Pit enters tapped.
{T}, Sacrifice Rocky Tar Pit: Search your library for a Swamp or Mountain card, put it onto the battlefield, then shuffle.

Malevolent Whispers

Gain control of target creature until end of turn. Untap that creature. It gets +2/+0 and gains haste until end of turn.
Madness {3}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Skulltap

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Zealous Conscripts

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

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of each of your postcombat main phases, add {R} for each 1 life your opponents have lost this turn.

Act of Aggression

({R/P} can be paid with either {R} or 2 life.)
Gain control of target creature an opponent controls until end of turn. Untap that creature. It gains haste until end of turn.

Mogis, God of Slaughter

Indestructible
As long as your devotion to black and red is less than seven, Mogis isn't a creature.
At the beginning of each opponent's upkeep, Mogis deals 2 damage to that player unless they sacrifice a creature of their choice.

Plague Spitter

At the beginning of your upkeep, Plague Spitter deals 1 damage to each creature and each player.
When Plague Spitter dies, it deals 1 damage to each creature and each player.

Soulreaper of Mogis

{2}{B}, Sacrifice a creature: Draw a card.

Mind Slash

{B}, Sacrifice a creature: Target opponent reveals their hand. You choose a card from it. That player discards that card. Activate only as a sorcery.

Neheb, Dreadhorde Champion

Trample
Whenever Neheb, Dreadhorde Champion deals combat damage to a player or planeswalker, you may discard any number of cards. If you do, draw that many cards and add that much {R}. Until end of turn, you don't lose this mana as steps and phases end.

Manaforge Cinder

{1}: Add {B} or {R}. Activate no more than three times each turn.

Star Compass

Star Compass enters tapped.
{T}: Add one mana of any color that a basic land you control could produce.

Temporary Insanity

Untap target creature with power less than the number of cards in your graveyard and gain control of it until end of turn. That creature gains haste until end of turn.

Read the Bones

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

Tymaret, the Murder King

{1}{R}, Sacrifice another creature: Tymaret, the Murder King deals 2 damage to target player or planeswalker.
{1}{B}, Sacrifice a creature: Return Tymaret from your graveyard to your hand.

Sol Ring

Rakdos, Lord of Riots

You can't cast Rakdos, Lord of Riots unless an opponent lost life this turn.
Flying, trample
Creature spells you cast cost {1} less to cast for each 1 life your opponents have lost this turn.