Blood Clock

At the beginning of each player's upkeep, that player returns a permanent they control to its owner's hand unless they pay 2 life.

Empowered Autogenerator

Empowered Autogenerator enters tapped.
{T}: Put a charge counter on Empowered Autogenerator. Add X mana of any one color, where X is the number of charge counters on Empowered Autogenerator.

Mirror Gallery

Koth of the Hammer

+1: Untap target Mountain. It becomes a 4/4 red Elemental creature until end of turn. It's still a land.
−2: Add {R} for each Mountain you control.
−5: You get an emblem with "Mountains you control have '{T}: This land deals 1 damage to any target.'"

Seething Anger

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.)
Target creature gets +3/+0 until end of turn.

Rush of Blood

Target creature gets +X/+0 until end of turn, where X is its power.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Fists of the Anvil

Target creature gets +4/+0 until end of turn.

Dictate of the Twin Gods

Flash
If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Shattering Spree

Replicate {R} (When you cast this spell, copy it for each time you paid its replicate cost. You may choose new targets for the copies.)
Destroy target artifact.

Blade of Selves

Equipped creature has myriad. (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.)
Equip {4}

Goblin Engineer

When Goblin Engineer enters, you may search your library for an artifact card, put it into your graveyard, then shuffle.
{R}, {T}, Sacrifice an artifact: Return target artifact card with mana value 3 or less from your graveyard to the battlefield.

Feldon of the Third Path

{2}{R}, {T}: Create a token that's a copy of target creature card in your graveyard, except it's an artifact in addition to its other types. It gains haste. Sacrifice it at the beginning of the next end step.

Viashino Heretic

{1}{R}, {T}: Destroy target artifact. Viashino Heretic deals damage to that artifact's controller equal to the artifact's mana value.

Moonsilver Key

{1}, {T}, Sacrifice Moonsilver Key: Search your library for an artifact card with a mana ability or a basic land card, reveal it, put it into your hand, then shuffle.

Mountain

Braid of Fire

Cumulative upkeep—Add {R}. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

Conjurer's Closet

At the beginning of your end step, you may exile target creature you control, then return that card to the battlefield under your control.

Unleash Fury

Double the power of target creature until end of turn.

Splinter Twin

Enchant creature
Enchanted creature has "{T}: Create a token that's a copy of this creature, except it has haste. Exile that token at the beginning of the next end step."

Hazoret's Monument

Red creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, you may discard a card. If you do, draw a card.

Thud

As an additional cost to cast this spell, sacrifice a creature.
Thud deals damage equal to the sacrificed creature's power to any target.

Torbran, Thane of Red Fell

If a red source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.

Iron Myr

Battlemage's Bracers

Equipped creature has haste.
Whenever an ability of equipped creature is activated, if it isn't a mana ability, you may pay {1}. If you do, copy that ability. You may choose new targets for the copy.
Equip {2}

Rowan, Fearless Sparkmage

+1: Up to one target creature gets +3/+0 and gains first strike until end of turn.
−2: Rowan, Fearless Sparkmage deals 1 damage to each of up to two target creatures. Those creatures can't block this turn.
−9: Gain control of all creatures until end of turn. Untap them. They gain haste until end of turn.

Jhoira's Familiar

Flying
Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)

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.")

Dragon Mask

{3}, {T}: Target creature you control gets +2/+2 until end of turn. Return it to its owner's hand at the beginning of the next end step. (Return it only if it's on the battlefield.)

Dong Zhou, the Tyrant

When Dong Zhou, the Tyrant enters, target creature an opponent controls deals damage equal to its power to that player.

Alpha Brawl

Target creature an opponent controls deals damage equal to its power to each other creature that player controls, then each of those creatures deals damage equal to its power to that creature.

Chandra, Bold Pyromancer

+1: Add {R}{R}. Chandra, Bold Pyromancer deals 2 damage to target player.
−3: Chandra, Bold Pyromancer deals 3 damage to target creature or planeswalker.
−7: Chandra, Bold Pyromancer deals 10 damage to target player and each creature and planeswalker they control.

Fling

As an additional cost to cast this spell, sacrifice a creature.
Fling deals damage equal to the sacrificed creature's power to any target.

Madblind Mountain

({T}: Add {R}.)
Madblind Mountain enters tapped.
{R}, {T}: Shuffle your library. Activate only if you control two or more red permanents.

Palladium Myr

Treasonous Ogre

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)
Pay 3 life: Add {R}.

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.)

Oni of Wild Places

Haste
At the beginning of your upkeep, return a red creature you control to its owner's hand.

Astral Cornucopia

Astral Cornucopia enters with X charge counters on it.
{T}: Choose a color. Add one mana of that color for each charge counter on Astral Cornucopia.

Reckless Charge

Target creature gets +3/+0 and gains haste until end of turn.
Flashback {2}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Manabarbs

Whenever a player taps a land for mana, Manabarbs deals 1 damage to that player.

Flameshadow Conjuring

Whenever a nontoken creature you control enters, you may pay {R}. If you do, create a token that's a copy of that creature. That token gains haste. Exile it at the beginning of the next end step.

Mana Geyser

Add {R} for each tapped land your opponents control.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Zo-Zu the Punisher

Whenever a land enters, Zo-Zu the Punisher deals 2 damage to that land's controller.

Ghitu War Cry

{R}: Target creature gets +1/+0 until end of turn.

Sol Ring

Fellwar Stone

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

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.

Titan's Strength

Target creature gets +3/+1 until end of turn. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Twinflame

Strive — This spell costs {2}{R} more to cast for each target beyond the first.
Choose any number of target creatures you control. For each of them, create a token that's a copy of that creature, except it has haste. Exile those tokens at the beginning of the next end step.

Erratic Portal

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

Brute Force

Target creature gets +3/+3 until end of turn.

Fire Diamond

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

Captive Flame

Burnished Hart

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

Infuriate

Target creature gets +3/+2 until end of turn.

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.

Heartless Hidetsugu

{T}: Heartless Hidetsugu deals damage to each player equal to half that player's life total, rounded down.

Doublecast

When you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.

Solemn Simulacrum

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

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

Heat Shimmer

Create a token that's a copy of target creature, except it has haste and "At the beginning of the end step, exile this permanent."

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Double Vision

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

Hijack

Gain control of target artifact or creature until end of turn. Untap it. It gains haste until end of turn.

Molten Echoes

As Molten Echoes enters, choose a creature type.
Whenever a nontoken creature you control of the chosen type enters, create a token that's a copy of that creature. That token gains haste. Exile it at the beginning of the next end step.

Fiery Conclusion

As an additional cost to cast this spell, sacrifice a creature.
Fiery Conclusion deals 5 damage to target creature.

Looming Spires

Looming Spires enters tapped.
When Looming Spires enters, target creature gets +1/+1 and gains first strike until end of turn.
{T}: Add {R}.

Cloud Key

As Cloud Key enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.

Imperial Recruiter

When Imperial Recruiter enters, search your library for a creature card with power 2 or less, reveal it, put it into your hand, then shuffle.