The Red Terror

Advanced Species — Whenever a red source you control deals damage to one or more permanents and/or players, put a +1/+1 counter on The Red Terror.

Ruby Medallion

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

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Jeska's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Add {R} for each card in target opponent's hand.
• Exile the top three cards of your library. You may play them this turn.

Acidic Soil

Acidic Soil deals damage to each player equal to the number of lands they control.

Platinum Angel

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

Madcap Experiment

Reveal cards from the top of your library until you reveal an artifact card. Put that card onto the battlefield and the rest on the bottom of your library in a random order. Madcap Experiment deals damage to you equal to the number of cards revealed this way.

Mountain

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Manabarbs

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

Platinum Emperion

Your life total can't change. (You can't gain or lose life. You can't pay any amount of life except 0.)

The Ozolith

Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on The Ozolith.
At the beginning of combat on your turn, if The Ozolith has counters on it, you may move all counters from The Ozolith onto target creature.

Burning Earth

Whenever a player taps a nonbasic land for mana, Burning Earth deals 1 damage to that player.

War Room

{T}: Add {C}.
{3}, {T}, Pay life equal to the number of colors in your commanders' color identity: Draw a card.

Dockside Extortionist

When Dockside Extortionist enters, create X Treasure tokens, where X is the number of artifacts and enchantments your opponents control. (Treasure tokens are artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Witch's Clinic

{T}: Add {C}.
{2}, {T}: Target commander gains lifelink until end of turn.

Fiery Emancipation

If a source you control would deal damage to a permanent or player, it deals triple that damage to that permanent or player instead.

Price of Progress

Price of Progress deals damage to each player equal to twice the number of nonbasic lands that player controls.

Jeska, Thrice Reborn

Jeska, Thrice Reborn enters with a loyalty counter on her for each time you've cast a commander from the command zone this game.
0: Choose target creature. Until your next turn, if that creature would deal combat damage to one of your opponents, it deals triple that damage to that player instead.
−X: Jeska, Thrice Reborn deals X damage to each of up to three targets.
Jeska, Thrice Reborn can be your commander.
Partner

Illusionist's Bracers

Whenever an ability of equipped creature is activated, if it isn't a mana ability, copy that ability. You may choose new targets for the copy.
Equip {3}

Gamble

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

Pyrohemia

At the beginning of the end step, if no creatures are on the battlefield, sacrifice Pyrohemia.
{R}: Pyrohemia deals 1 damage to each creature and each player.

Rampaging Ferocidon

Menace
Players can't gain life.
Whenever another creature enters, Rampaging Ferocidon deals 1 damage to that creature's controller.

Descent into Avernus

At the beginning of your upkeep, put two descent counters on Descent into Avernus. Then each player creates X Treasure tokens and Descent into Avernus deals X damage to each player, where X is the number of descent counters on Descent into Avernus.

Stuffy Doll

Indestructible
As Stuffy Doll enters, choose a player.
Whenever Stuffy Doll is dealt damage, it deals that much damage to the chosen player.
{T}: Stuffy Doll deals 1 damage to itself.

Wheel of Misfortune

Each player secretly chooses a number 0 or greater, then all players reveal those numbers simultaneously and determine the highest and lowest numbers revealed this way. Wheel of Misfortune deals damage equal to the highest number to each player who chose that number. Each player who didn't choose the lowest number discards their hand, then draws seven cards.

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.)

Citadel of Pain

At the beginning of each player's end step, Citadel of Pain deals X damage to that player, where X is the number of untapped lands they control.

Repercussion

Whenever a creature is dealt damage, Repercussion deals that much damage to that creature's controller.

Heartless Hidetsugu

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

Fiendish Duo

First strike
If a source would deal damage to an opponent, it deals double that damage to that player instead.

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.

Volcano Hellion

Volcano Hellion has echo {X}, where X is your life total. (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When Volcano Hellion enters, it deals an amount of damage of your choice to you and target creature. The damage can't be prevented.

Darksteel Plate

Indestructible
Equipped creature has indestructible.
Equip {2}

Batterbone

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/+1 and has vigilance and lifelink.
Equip {5}

Batterskull

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +4/+4 and has vigilance and lifelink.
{3}: Return Batterskull to its owner's hand.
Equip {5}

Magus of the Wheel

{1}{R}, {T}, Sacrifice Magus of the Wheel: Each player discards their hand, then draws seven cards.

Humble Defector

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

Resurrection Orb

Equipped creature has lifelink.
Whenever equipped creature dies, return that card to the battlefield under its owner's control at the beginning of the next end step.
Equip {4} ({4}: Attach to target creature you control. Equip only as a sorcery.)

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Urza's Saga gains "{T}: Add {C}."
II — Urza's Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This creature gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Sokenzan, Crucible of Defiance

{T}: Add {R}.
Channel — {3}{R}, Discard Sokenzan, Crucible of Defiance: Create two 1/1 colorless Spirit creature tokens. They gain haste until end of turn. This ability costs {1} less to activate for each legendary creature you control.

Mind's Eye

Whenever an opponent draws a card, you may pay {1}. If you do, draw a card.

Goblin Artillery

{T}: Goblin Artillery deals 2 damage to any target and 3 damage to you.

Endless Atlas

{2}, {T}: Draw a card. Activate only if you control three or more lands with the same name.

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.

Red Elemental Blast

Choose one —
• Counter target blue spell.
• Destroy target blue permanent.

Fortune Thief

Damage that would reduce your life total to less than 1 reduces it to 1 instead.
Morph {R}{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.)

Orcish Artillery

{T}: Orcish Artillery deals 2 damage to any target and 3 damage to you.

Unexpected Windfall

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 artifact: Add one mana of any color.")

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.

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.")

Thousand-Year Elixir

You may activate abilities of creatures you control as though those creatures had haste.
{1}, {T}: Untap target creature.

Exocrine

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Bio-plasmic Barrage — When Exocrine enters, it deals X damage to each player and each other creature.

Brash Taunter

Indestructible
Whenever Brash Taunter is dealt damage, it deals that much damage to target opponent.
{2}{R}, {T}: Brash Taunter fights another target creature.

Auntie Blyte, Bad Influence

Flying
Whenever a source you control deals damage to you, put that many +1/+1 counters on Auntie Blyte, Bad Influence.
{1}{R}, {T}, Remove X +1/+1 counters from Auntie Blyte: It deals X damage to any target.

Ankh of Mishra

Whenever a land enters, Ankh of Mishra deals 2 damage to that land's controller.

Pyroblast

Choose one —
• Counter target spell if it's blue.
• Destroy target permanent if it's blue.

Court of Ire

When Court of Ire enters, 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.

Roiling Vortex

At the beginning of each player's upkeep, Roiling Vortex deals 1 damage to them.
Whenever a player casts a spell, if no mana was spent to cast that spell, Roiling Vortex deals 5 damage to that player.
{R}: Your opponents can't gain life this turn.

Mana Vault

Mana Vault doesn't untap during your untap step.
At the beginning of your upkeep, you may pay {4}. If you do, untap Mana Vault.
At the beginning of your draw step, if Mana Vault is tapped, it deals 1 damage to you.
{T}: Add {C}{C}{C}.

Loxodon Warhammer

Equipped creature gets +3/+0 and has trample and lifelink.
Equip {3}

Rolling Earthquake

Rolling Earthquake deals X damage to each creature without horsemanship and each player.

Spear Spewer

Defender
{T}: Spear Spewer deals 1 damage to each player.

Earthquake

Earthquake deals X damage to each creature without flying and each player.

Basilisk Collar

Equipped creature has deathtouch and lifelink.
Equip {2}

Shadowspear

Equipped creature gets +1/+1 and has trample and lifelink.
{1}: Permanents your opponents control lose hexproof and indestructible until end of turn.
Equip {2}

Rogue's Passage

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

Rug of Smothering

Flying
Whenever a player casts a spell, they lose 1 life for each spell they've cast this turn.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control.)
Equip {1}

Spellshock

Whenever a player casts a spell, Spellshock deals 2 damage to that player.

Scavenged Brawler

Flying, vigilance, trample, lifelink
{5}, Exile Scavenged Brawler from your graveyard: Choose target creature. Put four +1/+1 counters, a flying counter, a vigilance counter, a trample counter, and a lifelink counter on that creature. Activate only as a sorcery.

Valakut, the Molten Pinnacle

Valakut, the Molten Pinnacle enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have Valakut, the Molten Pinnacle deal 3 damage to any target.
{T}: Add {R}.

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.
{T}: Add {C}{C}.

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.

Sol Ring

Chandra's Incinerator

This spell costs {X} less to cast, where X is the total amount of noncombat damage dealt to your opponents this turn.
Trample
Whenever a source you control deals noncombat damage to an opponent, Chandra's Incinerator deals that much damage to target creature or planeswalker that player controls.

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}