Thermo-Alchemist

Defender
{T}: This creature deals 1 damage to each opponent.
Whenever you cast an instant or sorcery spell, untap this creature.

Desperate Ritual

Add {R}{R}{R}.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Rite of Flame

Add {R}{R}, then add {R} for each card named Rite of Flame in each graveyard.

Crimson Wisps

Target creature becomes red and gains haste until end of turn. (It can attack and {T} this turn.)
Draw a card.

Wrenn's Resolve

Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Tectonic Hazard

Tectonic Hazard deals 1 damage to each opponent and each creature they control.

Simian Spirit Guide

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Magmatic Insight

As an additional cost to cast this spell, discard a land card.
Draw two cards.

Firebrand Archer

Whenever you cast a noncreature spell, this creature deals 1 damage to each opponent.