Have

Vexing Devil

When Vexing Devil enters, any opponent may have it deal 4 damage to them. If a player does, sacrifice Vexing Devil.

Guttersnipe

Whenever you cast an instant or sorcery spell, this creature deals 2 damage to each opponent.

Mudbutton Torchrunner

When Mudbutton Torchrunner dies, it deals 3 damage to any target.

Dragon's Claw

Whenever a player casts a red spell, you may gain 1 life.

Chandra's Pyrohelix

Chandra's Pyrohelix deals 2 damage divided as you choose among one or two targets.

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.

Leyline of Punishment

If Leyline of Punishment is in your opening hand, you may begin the game with it on the battlefield.
Players can't gain life.
Damage can't be prevented.

Risk Factor

Target opponent may have Risk Factor deal 4 damage to them. If that player doesn't, you draw three cards.
Jump-start (You may cast this card from your graveyard by discarding a card in addition to paying its other costs. Then exile this card.)

Lava Spike

Lava Spike deals 3 damage to target player or planeswalker.

Myriad Landscape

Myriad Landscape enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Mountain

Lightning Strike

Lightning Strike deals 3 damage to any target.

Beacon of Destruction

Beacon of Destruction deals 5 damage to any target. Shuffle Beacon of Destruction into its owner's library.

Curse of Bloodletting

Enchant player
If a source would deal damage to enchanted player, it deals double that damage to that player instead.

Sunbird's Invocation

Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

Banefire

Banefire deals X damage to any target.
If X is 5 or more, this spell can't be countered and the damage can't be prevented.

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of each of your postcombat main phases, add {R} for each 1 life your opponents have lost this turn.

Thran Dynamo

Madblind Mountain

({T}: Add {R}.)
Madblind Mountain enters tapped.
{R}, {T}: Shuffle your library. Activate only if you control two or more red permanents.