Thrill of Possibility

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

Chandra's Spitfire

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

Geosurge

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

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.

Dragon Hatchling

Flying
{R}: Dragon Hatchling gets +1/+0 until end of turn.

Tin Street Dodger

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

Phoenix Chick

Flying, haste
Phoenix Chick can't block.
Whenever you attack with three or more creatures, you may pay {R}{R}. If you do, return Phoenix Chick from your graveyard to the battlefield tapped and attacking with a +1/+1 counter on it.

Drakuseth, Maw of Flames

Flying
Whenever Drakuseth attacks, it deals 4 damage to any target and 3 damage to each of up to two other targets.

Bomat Courier

Haste
Whenever Bomat Courier attacks, exile the top card of your library face down. (You can't look at it.)
{R}, Discard your hand, Sacrifice Bomat Courier: Put all cards exiled with Bomat Courier into their owners' hands.

Mountain

Satyr's Cunning

Create a 1/1 red Satyr creature token with "This creature can't block."
Escape—{2}{R}, Exile two other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

Voldaren Stinger

Voldaren Stinger has first strike as long as it's attacking.
{2}{R}: Voldaren Stinger gets +2/+0 until end of turn.

Chandra, Roaring Flame

+1: Chandra, Roaring Flame deals 2 damage to target player or planeswalker.
−2: Chandra, Roaring Flame deals 2 damage to target creature.
−7: Chandra, Roaring Flame deals 6 damage to each opponent. Each player dealt damage this way gets an emblem with "At the beginning of your upkeep, this emblem deals 3 damage to you."

Chandra, Fire of Kaladesh

Whenever you cast a red spell, untap Chandra, Fire of Kaladesh.
{T}: Chandra, Fire of Kaladesh deals 1 damage to target player or planeswalker. If Chandra has dealt 3 or more damage this turn, exile her, then return her to the battlefield transformed under her owner's control.

Chandra, Fire of Kaladesh // Chandra, Roaring Flame

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.

Keldon Marauders

Vanishing 2 (This creature enters with two time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When Keldon Marauders enters or leaves the battlefield, it deals 1 damage to target player or planeswalker.

Scorch Spitter

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