Mountain

Chandra's Outrage

Chandra's Outrage deals 4 damage to target creature and 2 damage to that creature's controller.

Brimstone Volley

Brimstone Volley deals 3 damage to any target.
Morbid — Brimstone Volley deals 5 damage instead if a creature died this turn.

Bring Low

Bring Low deals 3 damage to target creature. If that creature has a +1/+1 counter on it, Bring Low deals 5 damage to it instead.

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.)

Impetuous Sunchaser

Flying, haste
Impetuous Sunchaser attacks each combat if able.

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.)

Act of Treason

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. (It can attack and {T} this turn.)

Flameborn Hellion

Haste
Flameborn Hellion attacks each combat if able.

Sudden Shock

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Sudden Shock deals 2 damage to any target.

Grotag Thrasher

Whenever Grotag Thrasher attacks, target creature can't block this turn.

Conflagrate

Conflagrate deals X damage divided as you choose among any number of targets.
Flashback—{R}{R}, Discard X cards. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Boulderfall

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

Lava Axe

Lava Axe deals 5 damage to target player or planeswalker.

Stonewright

Soulbond (You may pair this creature with another unpaired creature when either enters. They remain paired for as long as you control both of them.)
As long as Stonewright is paired with another creature, each of those creatures has "{R}: This creature gets +1/+0 until end of turn."

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.

Scouring Sands

Scouring Sands deals 1 damage to each creature your opponents control. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Bloodpyre Elemental

Sacrifice Bloodpyre Elemental: It deals 4 damage to target creature. Activate only as a sorcery.

Shock

Thatcher Revolt

Create three 1/1 red Human creature tokens with haste. Sacrifice those tokens at the beginning of the next end step.

Heat Ray

Heat Ray deals X damage to target creature.

Torrent of Stone

Torrent of Stone deals 4 damage to target creature.
Splice onto Arcane—Sacrifice two Mountains. (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Barrage of Boulders

Barrage of Boulders deals 1 damage to each creature you don't control.
Ferocious — If you control a creature with power 4 or greater, creatures can't block this turn.

Ignite Memories

Target player reveals a card at random from their hand. Ignite Memories deals damage to that player equal to that card's mana value.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Demolish

Raging Poltergeist

Markov Warlord

Haste (This creature can attack and {T} as soon as it comes under your control.)
When Markov Warlord enters, up to two target creatures can't block this turn.

Slith Firewalker

Haste
Whenever Slith Firewalker deals combat damage to a player, put a +1/+1 counter on it.

Glacial Ray

Glacial Ray deals 2 damage to any target.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Shatter

Magma Spray

Magma Spray deals 2 damage to target creature. If that creature would die this turn, exile it instead.

Touch and Go

Destroy target land.
Gotcha — If an opponent touches their face, you may say "Gotcha!" When you do, return Touch and Go from your graveyard to your hand.

Infernal Plunge

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

Valley Dasher

Haste
Valley Dasher attacks each combat if able.

Splatter Thug

First strike
Unleash (You may have this creature enter with a +1/+1 counter on it. It can't block as long as it has a +1/+1 counter on it.)

Resounding Thunder

Resounding Thunder deals 3 damage to any target.
Cycling {5}{B}{R}{G} ({5}{B}{R}{G}, Discard this card: Draw a card.)
When you cycle Resounding Thunder, it deals 6 damage to any target.

Geistflame

Geistflame deals 1 damage to any target.
Flashback {3}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)