Thermo-Alchemist

Defender
{T}: Thermo-Alchemist deals 1 damage to each opponent.
Whenever you cast an instant or sorcery spell, untap Thermo-Alchemist.

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.'"

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.

Hermetic Study

Enchant creature
Enchanted creature has "{T}: This creature deals 1 damage to any target."

Viridian Longbow

Equipped creature has "{T}: This creature deals 1 damage to any target."
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery. This card enters unattached and stays on the battlefield if the creature leaves.)

Orcish Artillery

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

Zhur-Taa Druid

{T}: Add {G}.
Whenever you tap Zhur-Taa Druid for mana, it deals 1 damage to each opponent.

Rootwater Hunter

{T}: Rootwater Hunter deals 1 damage to any target.

Fallen Ferromancer

Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)
{1}{R}, {T}: Fallen Ferromancer deals 1 damage to any target.

Reveka, Wizard Savant

{T}: Reveka, Wizard Savant deals 2 damage to any target and doesn't untap during your next untap step.

Fledgling Mawcor

Flying
{T}: Fledgling Mawcor deals 1 damage to any target.
Morph {U}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Fiendish Duo

First strike (This creature deals combat damage before creatures without first strike.)
If a source would deal damage to an opponent, it deals double that damage to that player instead.

Walking Ballista

Walking Ballista enters with X +1/+1 counters on it.
{4}: Put a +1/+1 counter on Walking Ballista.
Remove a +1/+1 counter from Walking Ballista: It deals 1 damage to any target.

Firebrand Archer

Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.

Seer's Sundial

Landfall — Whenever a land you control enters, you may pay {2}. If you do, draw a card.

Slate of Ancestry

{4}, {T}, Discard your hand: Draw a card for each creature you control.

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.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Vithian Stinger

{T}: Vithian Stinger deals 1 damage to any target.
Unearth {1}{R} ({1}{R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Iron Myr

Staff of Nin

At the beginning of your upkeep, draw a card.
{T}: Staff of Nin deals 1 damage to any target.

Wildfire Elemental

Whenever an opponent is dealt noncombat damage, creatures you control get +1/+0 until end of turn.

Goblin Artillery

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

Sol Ring

Infiltration Lens

Whenever equipped creature becomes blocked by a creature, you may draw two cards.
Equip {1}

Curse of Bloodletting

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

Frostwielder

If a creature dealt damage by Frostwielder this turn would die, exile it instead.
{T}: Frostwielder deals 1 damage to any target.

Psionic Gift

Gratuitous Violence

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

Lightning Prowess

Enchant creature
Enchanted creature has haste and "{T}: This creature deals 1 damage to any target."

Tok-Tok, Volcano Born

Protection from red
If a red source would deal damage to a player, it deals that much damage plus 1 to that player instead.

Akki Lavarunner

Haste
Whenever Akki Lavarunner deals damage to an opponent, flip it.

Akki Lavarunner // Tok-Tok, Volcano Born

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.

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}.

Thornwind Faeries

Flying
{T}: Thornwind Faeries deals 1 damage to any target.

Daretti, Scrap Savant

+2: Discard up to two cards, then draw that many cards.
−2: Sacrifice an artifact. If you do, return target artifact card from your graveyard to the battlefield.
−10: You get an emblem with "Whenever an artifact is put into your graveyard from the battlefield, return that card to the battlefield at the beginning of the next end step."
Daretti, Scrap Savant can be your commander.

Fireslinger

{T}: Fireslinger deals 1 damage to any target and 1 damage to you.

Spear Spewer

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

Quicksilver Dagger

Enchant creature
Enchanted creature has "{T}: This creature deals 1 damage to target player or planeswalker. You draw a card."

Opportunist

{T}: Opportunist deals 1 damage to target creature that was dealt damage this turn.

The Immortal Sun

Players can't activate planeswalkers' loyalty abilities.
At the beginning of your draw step, draw an additional card.
Spells you cast cost {1} less to cast.
Creatures you control get +1/+1.

Infernal Plunge

As an additional cost to cast this spell, sacrifice a creature.
Add {R}{R}{R}.

Temple of the False God

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

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.

Niv-Mizzet, Parun

This spell can't be countered.
Flying
Whenever you draw a card, Niv-Mizzet, Parun deals 1 damage to any target.
Whenever a player casts an instant or sorcery spell, you draw a card.

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Wolfhunter's Quiver

Equipped creature has "{T}: This creature deals 1 damage to any target" and "{T}: This creature deals 3 damage to target Werewolf creature."
Equip {5}

Moraug, Fury of Akoum

Each creature you control gets +1/+0 for each time it has attacked this turn.
Landfall — Whenever a land you control enters, if it's your main phase, there's an additional combat phase after this phase. At the beginning of that combat, untap all creatures you control.

Kamahl, Pit Fighter

Haste (This creature can attack and {T} as soon as it comes under your control.)
{T}: Kamahl, Pit Fighter deals 3 damage to any target.

Manabarbs

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

Heavy Arbalest

Equipped creature doesn't untap during its controller's untap step.
Equipped creature has "{T}: This creature deals 2 damage to any target."
Equip {4}

Jeweled Lotus

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

Flame Fusillade

Until end of turn, permanents you control gain "{T}: This permanent deals 1 damage to any target."

Druidic Satchel

{2}, {T}: Reveal the top card of your library. If it's a creature card, create a 1/1 green Saproling creature token. If it's a land card, put that card onto the battlefield under your control. If it's a noncreature, nonland card, you gain 2 life.

Cinder Pyromancer

{T}: Cinder Pyromancer deals 1 damage to target player or planeswalker.
Whenever you cast a red spell, you may untap Cinder Pyromancer.

Chandra's Spitfire

Flying
Whenever an opponent is dealt noncombat damage, Chandra's Spitfire gets +3/+0 until end of turn.

Anaba Shaman

{R}, {T}: Anaba Shaman deals 1 damage to any target.

Fire Whip

Enchant creature you control
Enchanted creature has "{T}: This creature deals 1 damage to any target."
Sacrifice Fire Whip: Fire Whip deals 1 damage to any target.

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.)

Nettle Drone

Devoid (This card has no color.)
{T}: Nettle Drone deals 1 damage to each opponent.
Whenever you cast a colorless spell, untap Nettle Drone.

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.

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.

Cunning Sparkmage

Haste
{T}: Cunning Sparkmage deals 1 damage to any target.

Mind's Eye

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

Matsu-Tribe Sniper

{T}: Matsu-Tribe Sniper deals 1 damage to target creature with flying.
Whenever Matsu-Tribe Sniper deals damage to a creature, tap that creature and it doesn't untap during its controller's next untap step.

Chandra, Roaring Flame

+1: Chandra, Roaring Flame deals 2 damage to target player or planeswalker.
−2: Chandra, Roaring Flame deals 2 damage to target creature.
−7: Chandra, Roaring Flame deals 6 damage to each opponent. Each player dealt damage this way gets an emblem with "At the beginning of your upkeep, this emblem deals 3 damage to you."

Chandra, Fire of Kaladesh

Whenever you cast a red spell, untap Chandra, Fire of Kaladesh.
{T}: Chandra, Fire of Kaladesh deals 1 damage to target player or planeswalker. If Chandra has dealt 3 or more damage this turn, exile her, then return her to the battlefield transformed under her owner's control.

Chandra, Fire of Kaladesh // Chandra, Roaring Flame

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.

Stun Sniper

{1}, {T}: Stun Sniper deals 1 damage to target creature. Tap that creature.

Crackling Perimeter

Tap an untapped Gate you control: Crackling Perimeter deals 1 damage to each opponent.

Angrath's Marauders

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

Lightning Crafter

Champion a Goblin or Shaman (When this enters, sacrifice it unless you exile another Goblin or Shaman you control. When this leaves the battlefield, that card returns to the battlefield.)
{T}: Lightning Crafter deals 3 damage to any target.

Jeska, Warrior Adept

First strike, haste
{T}: Jeska, Warrior Adept deals 1 damage to any target.

Endbringer

Untap Endbringer during each other player's untap step.
{T}: Endbringer deals 1 damage to any target.
{C}, {T}: Target creature can't attack or block this turn.
{C}{C}, {T}: Draw a card.

Sulfuric Vapors

If a red spell would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead.

Hypervolt Grasp

Enchant creature
Enchanted creature has "{T}: This creature deals 1 damage to any target."
{1}{U}: Return Hypervolt Grasp to its owner's hand.

Prodigal Pyromancer

{T}: Prodigal Pyromancer deals 1 damage to any target.

Fervent Paincaster

{T}: Fervent Paincaster deals 1 damage to target player or planeswalker.
{T}, Exert Fervent Paincaster: It deals 1 damage to target creature. (An exerted creature won't untap during your next untap step.)

Ben-Ben, Akki Hermit

{T}: Ben-Ben, Akki Hermit deals damage to target attacking creature equal to the number of untapped Mountains you control.

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.

Lightning-Rig Crew

{T}: Lightning-Rig Crew deals 1 damage to each opponent.
Whenever you cast a Pirate spell, untap Lightning-Rig Crew.

Silverclad Ferocidons

Enrage — Whenever Silverclad Ferocidons is dealt damage, each opponent sacrifices a permanent of their choice.

Blisterspit Gremlin

{1}, {T}: Blisterspit Gremlin deals 1 damage to each opponent.
Whenever you cast a noncreature spell, untap Blisterspit Gremlin.

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}.

Mountain

Rakdos Ickspitter

{T}: Rakdos Ickspitter deals 1 damage to target creature and that creature's controller loses 1 life.

Quicksmith Rebel

When Quicksmith Rebel enters, target artifact you control gains "{T}: This artifact deals 2 damage to any target" for as long as you control Quicksmith Rebel.

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, Venerated Firemage deals 2 damage to any target.

Sword of Fire and Ice

Equipped creature gets +2/+2 and has protection from red and from blue.
Whenever equipped creature deals combat damage to a player, Sword of Fire and Ice deals 2 damage to any target and you draw a card.
Equip {2}

Burning Earth

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

Geosurge

Add {R}{R}{R}{R}{R}{R}{R}. Spend this mana only to cast artifact or creature spells.

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.

Goblin Fireslinger

{T}: Goblin Fireslinger deals 1 damage to target player or planeswalker.

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.

Mawcor

Flying
{T}: Mawcor deals 1 damage to any target.

Mask of Memory

Whenever equipped creature deals combat damage to a player, you may draw two cards. If you do, discard a card.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Burning Anger

Enchant creature
Enchanted creature has "{T}: This creature deals damage equal to its power to any target."

Whipkeeper

{T}: Whipkeeper deals damage to target creature equal to the damage already dealt to it this turn.