Spitebellows

When this creature leaves the battlefield, it deals 6 damage to target creature.
Evoke {1}{R}{R} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters.)

Generator Servant

{T}, Sacrifice this creature: Add {C}{C}. If that mana is spent on a creature spell, it gains haste until end of turn. (That creature can attack and {T} as soon as it comes under your control.)

Sootstoke Kindler

Haste
{T}: Target black or red creature gains haste until end of turn.

Inside Out

Switch target creature's power and toughness until end of turn.
Draw a card.

Swamp

Manamorphose

Add two mana in any combination of colors.
Draw a card.

Igneous Pouncer

Haste
Swampcycling {2}, mountaincycling {2} ({2}, Discard this card: Search your library for a Swamp or Mountain card, reveal it, put it into your hand, then shuffle.)

Book Burning

Any player may have Book Burning deal 6 damage to them. If no one does, target player mills six cards.

Mountain

Sunflare Shaman

{1}{R}, {T}: This creature deals X damage to any target and X damage to itself, where X is the number of Elemental cards in your graveyard.

Spark Elemental

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

Burning Inquiry

Each player draws three cards, then discards three cards at random.

Manaforge Cinder

{1}: Add {B} or {R}. Activate no more than three times each turn.

Akoum Hellhound

Landfall — Whenever a land you control enters, this creature gets +2/+2 until end of turn.

Balustrade Spy

Flying
When this creature enters, target player reveals cards from the top of their library until they reveal a land card, then puts those cards into their graveyard.