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.")

Diabolic Intent

As an additional cost to cast this spell, sacrifice a creature.
Search your library for a card, put that card into your hand, then shuffle.

Smash to Dust

Choose one —
• Destroy target artifact.
• Destroy target creature with defender.
• Smash to Dust deals 1 damage to each creature your opponents control.

End the Festivities

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

Bump in the Night

Target opponent loses 3 life.
Flashback {5}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Dreadhorde Butcher

Haste
Whenever Dreadhorde Butcher deals combat damage to a player or planeswalker, put a +1/+1 counter on Dreadhorde Butcher.
When Dreadhorde Butcher dies, it deals damage equal to its power to any target.

Unearth

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Swamp

Pestilent Spirit

Menace, deathtouch
Instant and sorcery spells you control have deathtouch. (Any amount of damage they deal to a creature is enough to destroy it.)

Goblin Sharpshooter

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

Dark Ritual

Dagger Caster

When Dagger Caster enters, it deals 1 damage to each opponent and 1 damage to each creature your opponents control.