Lava Axe

Lava Axe deals 5 damage to target player or planeswalker.

Flames of the Firebrand

Flames of the Firebrand deals 3 damage divided as you choose among one, two, or three targets.

Paragon of Fierce Defiance

Other red creatures you control get +1/+1.
{R}, {T}: Another target red creature you control gains haste until end of turn. (It can attack and {T} this turn.)

Fall of the Hammer

Target creature you control deals damage equal to its power to another target creature.

Boulderfall

Boulderfall deals 5 damage divided as you choose among any number of targets.

Bolt of Keranos

Bolt of Keranos deals 3 damage to any target. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Pharagax Giant

Tribute 2 (As this creature enters, an opponent of your choice may put two +1/+1 counters on it.)
When Pharagax Giant enters, if tribute wasn't paid, Pharagax Giant deals 5 damage to each opponent.

Titan's Revenge

Titan's Revenge deals X damage to any target. Clash with an opponent. If you win, return Titan's Revenge to its owner's hand. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)

Magma Jet

Magma Jet deals 2 damage to any target. Scry 2.

Ghostfire

Ghostfire is colorless.
Ghostfire deals 3 damage to any target.

Lightning Strike

Lightning Strike deals 3 damage to any target.

Starfall

Starfall deals 3 damage to target creature. If that creature is an enchantment, Starfall deals 3 damage to that creature's controller.

Thornbite Staff

Equipped creature has "{2}, {T}: This creature deals 1 damage to any target" and "Whenever a creature dies, untap this creature."
Whenever a Shaman creature enters, you may attach Thornbite Staff to it.
Equip {4}

Taurean Mauler

Changeling (This card is every creature type.)
Whenever an opponent casts a spell, you may put a +1/+1 counter on this creature.

Volt Charge

Volt Charge deals 3 damage to any target. Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Power of Fire

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

Staff of the Flame Magus

Whenever you cast a red spell or a Mountain you control enters, you gain 1 life.

Fire Juggler

Whenever Fire Juggler becomes blocked, clash with an opponent. If you win, Fire Juggler deals 4 damage to each creature blocking it. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher mana value.)

Lightning Volley

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

Spellbinder

Imprint — When Spellbinder enters, you may exile an instant card from your hand.
Whenever equipped creature deals combat damage to a player, you may copy the exiled card. If you do, you may cast the copy without paying its mana cost.
Equip {4}

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.

Cone of Flame

Cone of Flame deals 1 damage to any target, 2 damage to another target, and 3 damage to a third target.

Emberwilde Augur

Sacrifice Emberwilde Augur: It deals 3 damage to target player or planeswalker. Activate only during your upkeep.

Inferno Titan

{R}: Inferno Titan gets +1/+0 until end of turn.
Whenever Inferno Titan enters or attacks, it deals 3 damage divided as you choose among one, two, or three targets.

Rage Forger

When Rage Forger enters, put a +1/+1 counter on each other Shaman creature you control.
Whenever a creature you control with a +1/+1 counter on it attacks, you may have that creature deal 1 damage to target player or planeswalker.