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.)

Naturalize

Seal of Fire

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

Have

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.)

Incinerate

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

Karplusan Forest

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

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.

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.

Mountain

Fireblast

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

Kindle

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

Forest

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.

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.

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.