Mountain

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Pillar of Flame

Pillar of Flame deals 2 damage to any target. If a creature dealt damage this way would die this turn, exile it instead.

Play with Fire

Play with Fire deals 2 damage to any target. If a player is dealt damage this way, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

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.'"

Lightning Strike

Lightning Strike deals 3 damage to any target.

Chandra, Torch of Defiance

+1: Exile the top card of your library. You may cast that card. If you don't, Chandra, Torch of Defiance deals 2 damage to each opponent.
+1: Add {R}{R}.
−3: Chandra, Torch of Defiance deals 4 damage to target creature.
−7: You get an emblem with "Whenever you cast a spell, this emblem deals 5 damage to any target."

Pyretic Ritual

Galvanic Blast

Galvanic Blast deals 2 damage to any target.
Metalcraft — Galvanic Blast deals 4 damage instead if you control three or more artifacts.

Vexing Devil

When Vexing Devil enters, any opponent may have it deal 4 damage to them. If a player does, sacrifice Vexing Devil.

Lava Spike

Lava Spike deals 3 damage to target player or planeswalker.

Slaying Fire

Slaying Fire deals 3 damage to any target.
Adamant — If at least three red mana was spent to cast this spell, it deals 4 damage instead.