Flame Burst

Flame Burst deals X damage to any target, where X is 2 plus the number of cards named Flame Burst in all graveyards.

Incinerate

Incinerate deals 3 damage to any target. A creature dealt damage this way can't be regenerated this turn.

Naturalize

Lava Dart

Lava Dart deals 1 damage to any target.
Flashback—Sacrifice a Mountain. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Oath of Druids

At the beginning of each player's upkeep, that player chooses target player who controls more creatures than they do and is their opponent. The first player may reveal cards from the top of their library until they reveal a creature card. If the first player does, that player puts that card onto the battlefield and all other cards revealed this way into their graveyard.

Fireblast

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

Forest

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Cursed Scroll

{3}, {T}: Choose a card name, then reveal a card at random from your hand. If that card has the chosen name, Cursed Scroll deals 2 damage to any target.

Wooded Foothills

{T}, Pay 1 life, Sacrifice Wooded Foothills: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Karplusan Forest

{T}: Add {C}.
{T}: Add {R} or {G}. Karplusan Forest deals 1 damage to you.

Kindle

Kindle deals X damage to any target, where X is 2 plus the number of cards named Kindle in all graveyards.

Mountain

Seal of Fire

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

Blistering Firecat

Trample, haste
At the beginning of the end step, sacrifice Blistering Firecat.
Morph {R}{R} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Ball Lightning

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Haste (This creature can attack and {T} as soon as it comes under your control.)
At the beginning of the end step, sacrifice this creature.