Electrickery

Electrickery deals 1 damage to target creature you don't control.
Overload {1}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Defiler of Instinct

First strike
As an additional cost to cast red permanent spells, you may pay 2 life. Those spells cost {R} less to cast if you paid life this way. This effect reduces only the amount of red mana you pay.
Whenever you cast a red permanent spell, this creature deals 1 damage to any target.

Electrostatic Field

Defender
Whenever you cast an instant or sorcery spell, this creature deals 1 damage to each opponent.

Thermo-Alchemist

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

End the Festivities

End the Festivities deals 1 damage to each opponent and each creature and planeswalker they control.

Sawblade Scamp

Haste
Whenever you cast a noncreature spell, put an oil counter on this creature.
{T}, Remove an oil counter from this creature: It deals 1 damage to each opponent.

Fiery Confluence

Choose three. You may choose the same mode more than once.
• Fiery Confluence deals 1 damage to each creature.
• Fiery Confluence deals 2 damage to each opponent.
• Destroy target artifact.

Scouring Sands

Scouring Sands deals 1 damage to each creature your opponents control. Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Seismic Wave

Seismic Wave deals 2 damage to any target and 1 damage to each nonartifact creature target opponent controls.

Goblin Sharpshooter

This creature doesn't untap during your untap step.
Whenever a creature dies, untap this creature.
{T}: This creature deals 1 damage to any target.

Tectonic Hazard

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

Unruly Catapult

Boiling Earth

Boiling Earth deals 1 damage to each creature your opponents control.
Awaken 4—{6}{R} (If you cast this spell for {6}{R}, also put four +1/+1 counters on target land you control and it becomes a 0/0 Elemental creature with haste. It's still a land.)

Cosmotronic Wave

Cosmotronic Wave deals 1 damage to each creature your opponents control. Creatures your opponents control can't block this turn.

Erebor Flamesmith

Whenever you cast an instant or sorcery spell, this creature deals 1 damage to each opponent.

Goblin Chainwhirler

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

Radiating Lightning

Radiating Lightning deals 3 damage to target player and 1 damage to each creature that player controls.

Goblin Fireslinger

{T}: This creature deals 1 damage to target player or planeswalker.

Fear, Fire, Foes!

Damage can't be prevented this turn. Fear, Fire, Foes! deals X damage to target creature and 1 damage to each other creature with the same controller.

Taii Wakeen, Perfect Shot

Whenever a source you control deals noncombat damage to a creature equal to that creature's toughness, draw a card.
{X}, {T}: If a source you control would deal noncombat damage to a permanent or player this turn, it deals that much damage plus X instead.

Blazing Volley

Blazing Volley deals 1 damage to each creature your opponents control.

Scattershot

Scattershot deals 1 damage to target creature.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Flame Jab

Flame Jab deals 1 damage to any target.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Firebrand Archer

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