Heartless Hidetsugu

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

Spinerock Knoll

Hideaway 4 (When this land enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.)
This land enters tapped.
{T}: Add {R}.
{R}, {T}: You may play the exiled card without paying its mana cost if an opponent was dealt 7 or more damage this 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.

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}

Jeweled Lotus

{T}, Sacrifice this artifact: Add three mana of any one color. Spend this mana only to cast your commander.

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.

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, this creature deals that much damage to target creature or planeswalker that player controls.

Plaza of Heroes

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a legendary spell.
{T}: Add one mana of any color among legendary permanents you control.
{3}, {T}, Exile this land: Target legendary creature gains hexproof and indestructible until end of turn.

Shatterskull, the Hammer Pass

As this land enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {R}.

Shatterskull Smashing

Shatterskull Smashing deals X damage divided as you choose among up to two target creatures and/or planeswalkers. If X is 6 or more, Shatterskull Smashing deals twice X damage divided as you choose among them instead.

Shatterskull Smashing // Shatterskull, the Hammer Pass

Mana Vault

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

Fanatic of Mogis

When this creature enters, it deals damage to each opponent equal to your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)

Roiling Vortex

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

Tunnel Ignus

Whenever a land enters under an opponent's control, if that player had another land enter the battlefield under their control this turn, this creature deals 3 damage to that player.

Radiant Performer

Flash
When this creature enters, if you cast it from your hand, choose target spell or ability that targets only a single permanent or player. Copy that spell or ability for each other permanent or player the spell or ability could target. Each copy targets a different one of those permanents and players.

Sol Ring

Curse of Shaken Faith

Enchant player
Whenever enchanted player casts a spell other than the first spell they cast each turn or copies a spell, this Aura deals 2 damage to them.

God-Pharaoh's Statue

Spells your opponents cast cost {2} more to cast.
At the beginning of your end step, each opponent loses 1 life.

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.

Immolation Shaman

Whenever an opponent activates an ability of an artifact, creature, or land that isn't a mana ability, this creature deals 1 damage to that player.
{3}{R}{R}: This creature gets +3/+3 and gains menace until end of turn.

Kazuul's Cliffs

Kazuul's Fury

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

Kazuul's Fury // Kazuul's Cliffs

Sokenzan, Crucible of Defiance

{T}: Add {R}.
Channel — {3}{R}, Discard this card: 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.

Banefire

Banefire deals X damage to any target.
If X is 5 or more, this spell can't be countered and the damage can't be prevented.

Cursed Mirror

{T}: Add {R}.
As this artifact enters, you may have it become a copy of any creature on the battlefield until end of turn, except it has haste.

Harsh Mentor

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

Lotus Petal

{T}, Sacrifice this artifact: Add one mana of any color.

Den of the Bugbear

If you control two or more other lands, this land enters tapped.
{T}: Add {R}.
{3}{R}: Until end of turn, this land becomes a 3/2 red Goblin creature with "Whenever this creature attacks, create a 1/1 red Goblin creature token that's tapped and attacking." It's still a land.

Cavern of Souls

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Chrome Mox

Imprint — When this artifact enters, you may exile a nonartifact, nonland card from your hand.
{T}: Add one mana of any of the exiled card's colors.

Shrine of Burning Rage

At the beginning of your upkeep and whenever you cast a red spell, put a charge counter on this artifact.
{3}, {T}, Sacrifice this artifact: It deals damage equal to the number of charge counters on it to any target.

Crimson Honor Guard

Trample
At the beginning of each player's end step, this creature deals 4 damage to that player unless they control a commander.

Mana Crypt

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

Basilisk Collar

Equipped creature has deathtouch and lifelink. (Any amount of damage it deals to a creature is enough to destroy it. Damage dealt by this creature also causes you to gain that much life.)
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Acidic Soil

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

Solphim, Mayhem Dominus

If a source you control would deal noncombat damage to an opponent or a permanent an opponent controls, it deals double that damage to that player or permanent instead.
{1}{R/P}{R/P}, Discard two cards: Put an indestructible counter on Solphim. ({R/P} can be paid with either {R} or 2 life.)

Stigma Lasher

Wither (This deals damage to creatures in the form of -1/-1 counters.)
Whenever this creature deals damage to a player, that player can't gain life for the rest of the game.

Crimson Fleet Commodore

Trample
When this creature enters, you become the monarch.

Emberwilde Captain

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

Tyrite Sanctum

{T}: Add {C}.
{2}, {T}: Target legendary creature becomes a God in addition to its other types. Put a +1/+1 counter on it.
{4}, {T}, Sacrifice this land: Put an indestructible counter on target God.

Commander's Plate

Equipped creature gets +3/+3 and has protection from each color that's not in your commander's color identity.
Equip commander {3}
Equip {5}

Rogue's Passage

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

Valakut Stoneforge

Valakut Awakening

Put any number of cards from your hand on the bottom of your library, then draw that many cards plus one.

Valakut Awakening // Valakut Stoneforge

Dwarven Mine

({T}: Add {R}.)
This land enters tapped unless you control three or more other Mountains.
When this land enters untapped, create a 1/1 red Dwarf creature token.

Furnace of Rath

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

Giant Cindermaw

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Players can't gain life.

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

Mechanized Warfare

If a red or artifact source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 1 instead.

Spellshock

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

Humble Defector

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

Sulfuric Vortex

At the beginning of each player's upkeep, this enchantment deals 2 damage to that player.
If a player would gain life, that player gains no life instead.

Lightning Greaves

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

Song-Mad Ruins

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

Eidolon of the Great Revel

Whenever a player casts a spell with mana value 3 or less, this creature deals 2 damage to that player.

Cemetery Gatekeeper

First strike
When this creature enters, exile a card from a graveyard.
Whenever a player plays a land or casts a spell, if it shares a card type with the exiled card, this creature deals 2 damage to that player.

Price of Progress

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

Field of Ruin

{T}: Add {C}.
{2}, {T}, Sacrifice this land: Destroy target nonbasic land an opponent controls. Each player searches their library for a basic land card, puts it onto the battlefield, then shuffles.

From the Ashes

Destroy all nonbasic lands. For each land destroyed this way, its controller may search their library for a basic land card and put it onto the battlefield. Then each player who searched their library this way shuffles.

Dualcaster Mage

Flash
When this creature enters, copy target instant or sorcery spell. You may choose new targets for the copy.

Pyrostatic Pillar

Whenever a player casts a spell with mana value 3 or less, this enchantment deals 2 damage to that player.

Life of the Party

First strike, trample, haste
Whenever this creature attacks, it gets +X/+0 until end of turn, where X is the number of creatures you control.
When this creature enters, if it's not a token, each opponent creates a token that's a copy of it. The tokens are goaded for the rest of the game. (They attack each combat if able and attack a player other than you if able.)

Leyline of Combustion

If this card is in your opening hand, you may begin the game with it on the battlefield.
Whenever you and/or at least one permanent you control becomes the target of a spell or ability an opponent controls, this enchantment deals 2 damage to that player.

Zo-Zu the Punisher

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

Court of Ire

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

Mutavault

{T}: Add {C}.
{1}: This land becomes a 2/2 creature with all creature types until end of turn. It's still a land.

Jaya, Venerated Firemage

If another red source you control would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.
−2: Jaya deals 2 damage to any target.

Mikokoro, Center of the Sea

{T}: Add {C}.
{2}, {T}: Each player draws a card.

Scab-Clan Berserker

Haste
Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
Whenever an opponent casts a noncreature spell, if this creature is renowned, this creature deals 2 damage to that player.

Mountain

Spikefield Cave

Spikefield Hazard

Spikefield Hazard deals 1 damage to any target. If a permanent dealt damage this way would die this turn, exile it instead.

Spikefield Hazard // Spikefield Cave

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — This Saga gains "{T}: Add {C}."
II — This Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This token 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.

Goblin Sharpshooter

This creature doesn't untap during your untap step.
Whenever a creature dies, untap this creature.
{T}: This creature deals 1 damage to any target.

Ankh of Mishra

Whenever a land enters, this artifact deals 2 damage to that land's controller.

Enchanter's Bane

At the beginning of your end step, target enchantment deals damage equal to its mana value to its controller unless that player sacrifices it.

Tome of Legends

This artifact enters with a page counter on it.
Whenever your commander enters or attacks, put a page counter on this artifact.
{1}, {T}, Remove a page counter from this artifact: Draw a card.

Embermaw Hellion

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
If another red source you control would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.

Gratuitous Violence

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

Tibalt, Rakish Instigator

Your opponents can't gain life.
−2: Create a 1/1 red Devil creature token with "When this token dies, it deals 1 damage to any target."

Leyline of Punishment

If this card is in your opening hand, you may begin the game with it on the battlefield.
Players can't gain life.
Damage can't be prevented.

Manabarbs

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

Burning Earth

Whenever a player taps a nonbasic land for mana, this enchantment deals 1 damage to that player.

Rampaging Ferocidon

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