Fires of Invention

You can cast spells only during your turn and you can cast no more than two spells each turn.
You may cast spells with mana value less than or equal to the number of lands you control without paying their mana costs.

Moonveil Dragon

Flying
{R}: Each creature you control gets +1/+0 until end of turn.

Gauntlet of Might

Red creatures get +1/+1.
Whenever a Mountain is tapped for mana, its controller adds an additional {R}.

Torbran, Thane of Red Fell

If a red source you control would deal damage to an opponent or a permanent an opponent controls, it deals that much damage plus 2 instead.

Bulwark

At the beginning of your upkeep, this enchantment deals X damage to target opponent, where X is the number of cards in your hand minus the number of cards in that player's hand.

Mordant Dragon

Flying
{1}{R}: This creature gets +1/+0 until end of turn.
Whenever this creature deals combat damage to a player, you may have it deal that much damage to target creature that player controls.

Myojin of Roaring Blades

Myojin of Roaring Blades enters with an indestructible counter on it if you cast it from your hand.
Remove an indestructible counter from Myojin of Roaring Blades: It deals 7 damage to each of up to three targets.

Clickslither

Haste
Sacrifice a Goblin: This creature gets +2/+2 and gains trample until end of turn.

Flowstone Overseer

{R}{R}: Target creature gets +1/-1 until end of turn.

Fiery Emancipation

If a source you control would deal damage to a permanent or player, it deals triple that damage to that permanent or player instead.

That Which Was Taken

{4}, {T}: Put a divinity counter on target permanent other than That Which Was Taken.
Each permanent with a divinity counter on it has indestructible.

Magmatic Force

At the beginning of each upkeep, this creature deals 3 damage to any target.

Cavalier of Flame

{1}{R}: Creatures you control get +1/+0 and gain haste until end of turn.
When this creature enters, discard any number of cards, then draw that many cards.
When this creature dies, it deals X damage to each opponent and each planeswalker they control, where X is the number of land cards in your graveyard.

Awaken the Ancient

Enchant Mountain
Enchanted Mountain is a 7/7 red Giant creature with haste. It's still a land.

Geosurge

Add {R}{R}{R}{R}{R}{R}{R}. Spend this mana only to cast artifact or creature spells.

Soulbright Flamekin

{2}: Target creature gains trample until end of turn. If this is the third time this ability has resolved this turn, you may add {R}{R}{R}{R}{R}{R}{R}{R}.

Kuldotha Phoenix

Flying, haste
Metalcraft — {4}: Return this card from your graveyard to the battlefield. Activate only during your upkeep and only if you control three or more artifacts.

Mountain

Nykthos, Shrine to Nyx

{T}: Add {C}.
{2}, {T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)

Myojin of Infinite Rage

Myojin of Infinite Rage enters with a divinity counter on it if you cast it from your hand.
Myojin of Infinite Rage has indestructible as long as it has a divinity counter on it.
Remove a divinity counter from Myojin of Infinite Rage: Destroy all lands.

Scourge of Valkas

Flying
Whenever this creature or another Dragon you control enters, it deals X damage to any target, where X is the number of Dragons you control.
{R}: This creature gets +1/+0 until end of turn.

Valakut, the Molten Pinnacle

This land enters tapped.
Whenever a Mountain you control enters, if you control at least five other Mountains, you may have this land deal 3 damage to any target.
{T}: Add {R}.

Goblin Chainwhirler

First strike
When this creature enters, it deals 1 damage to each opponent and each creature and planeswalker they control.