Fireblast

You may sacrifice two Mountains rather than pay this spell's mana cost.
Fireblast deals 4 damage to any target.

Goblin Guide

Haste
Whenever Goblin Guide attacks, defending player reveals the top card of their library. If it's a land card, that player puts it into their hand.

Molten Rain

Destroy target land. If that land was nonbasic, Molten Rain deals 2 damage to the land's controller.

Price of Progress

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

Needle Drop

Needle Drop deals 1 damage to any target that was dealt damage this turn.
Draw a card.

Searing Blaze

Searing Blaze deals 1 damage to target player or planeswalker and 1 damage to target creature that player or that planeswalker's controller controls.
Landfall — If you had a land enter the battlefield under your control this turn, Searing Blaze deals 3 damage to that player or planeswalker and 3 damage to that creature instead.

Relic of Progenitus

{T}: Target player exiles a card from their graveyard.
{1}, Exile Relic of Progenitus: Exile all graveyards. Draw a card.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Monastery Swiftspear

Haste
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Seal of Fire

Sacrifice Seal of Fire: It deals 2 damage to any target.

Searing Blood

Searing Blood deals 2 damage to target creature. When that creature dies this turn, Searing Blood deals 3 damage to the creature's controller.

Smash to Smithereens

Destroy target artifact. Smash to Smithereens deals 3 damage to that artifact's controller.

Lava Spike

Lava Spike deals 3 damage to target player or planeswalker.

Gorilla Shaman

{X}{X}{1}: Destroy target noncreature artifact with mana value X.

Pyroclasm

Pyroclasm deals 2 damage to each creature.

Exquisite Firecraft

Exquisite Firecraft deals 4 damage to any target.
Spell mastery — If there are two or more instant and/or sorcery cards in your graveyard, this spell can't be countered.

Kessig Flamebreather

Whenever you cast a noncreature spell, Kessig Flamebreather deals 1 damage to each opponent.

Tectonic Hazard

Tectonic Hazard deals 1 damage to each opponent and each creature they control.

Flame Rift

Flame Rift deals 4 damage to each player.

Chain Lightning

Chain Lightning deals 3 damage to any target. Then that player or that permanent's controller may pay {R}{R}. If the player does, they may copy this spell and may choose a new target for that copy.

Sulfuric Vortex

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

Skullcrack

Players can't gain life this turn. Damage can't be prevented this turn. Skullcrack deals 3 damage to target player or planeswalker.

Light Up the Stage

Spectacle {R} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Mountain

Skewer the Critics

Spectacle {R} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Skewer the Critics deals 3 damage to any target.

Voldaren Epicure

When Voldaren Epicure enters, it deals 1 damage to each opponent. Create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")

Rift Bolt

Rift Bolt deals 3 damage to any target.
Suspend 1—{R} (Rather than cast this card from your hand, you may pay {R} and exile it with a time counter on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Thermo-Alchemist

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