Heartfire

As an additional cost to cast this spell, sacrifice a creature or planeswalker.
Heartfire deals 4 damage to any target.

Shock

Footlight Fiend

When Footlight Fiend dies, it deals 1 damage to any target.

Play with Fire

Play with Fire deals 2 damage to any target. If a player is dealt damage this way, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Light Up the Stage

Spectacle {R} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Exile the top two cards of your library. Until the end of your next turn, you may play those cards.

Legion Warboss

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
At the beginning of combat on your turn, create a 1/1 red Goblin creature token. That token gains haste until end of turn and attacks this combat if able.

Cavalcade of Calamity

Whenever a creature you control with power 1 or less attacks, Cavalcade of Calamity deals 1 damage to the player or planeswalker that creature is attacking.

Torch Courier

Haste
Sacrifice Torch Courier: Another target creature gains haste until end of turn.

Goblin Instigator

When Goblin Instigator enters, create a 1/1 red Goblin creature token.

Tin Street Dodger

Haste
{R}: Tin Street Dodger can't be blocked this turn except by creatures with defender.

This spell can't be countered.
Fry deals 5 damage to target creature or planeswalker that's white or blue.

Mountain

Chandra's Spitfire

Flying
Whenever an opponent is dealt noncombat damage, Chandra's Spitfire gets +3/+0 until end of turn.

Chandra, Acolyte of Flame

0: Put a loyalty counter on each red planeswalker you control.
0: Create two 1/1 red Elemental creature tokens. They gain haste. Sacrifice them at the beginning of the next end step.
−2: You may cast target instant or sorcery card with mana value 3 or less from your graveyard. If that spell would be put into your graveyard, exile it instead.

Scorch Spitter

Whenever Scorch Spitter attacks, it deals 1 damage to the player or planeswalker it's attacking.

Chandra's Regulator

Whenever you activate a loyalty ability of a Chandra planeswalker, you may pay {1}. If you do, copy that ability. You may choose new targets for the copy.
{1}, {T}, Discard a Mountain card or a red card: Draw a card.