Lava Coil

Lava Coil deals 4 damage to target creature. If that creature would die this turn, exile it instead.

Lightning Strike

Lightning Strike deals 3 damage to any target.

Theater of Horrors

At the beginning of your upkeep, exile the top card of your library.
During your turn, if an opponent lost life this turn, you may play lands and cast spells from among cards exiled with Theater of Horrors.
{3}{R}: Theater of Horrors deals 1 damage to target opponent or planeswalker.

Bedevil

Destroy target artifact, creature, or planeswalker.

Dragonskull Summit

Dragonskull Summit enters the battlefield tapped unless you control a Swamp or a Mountain.
{T}: Add {B} or {R}.

Viashino Pyromancer

When Viashino Pyromancer enters the battlefield, it deals 2 damage to target player or planeswalker.

Blood Crypt

({T}: Add {B} or {R}.)
As Blood Crypt enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Fanatical Firebrand

Haste
{T}, Sacrifice Fanatical Firebrand: It deals 1 damage to any target.

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Skewer the Critics

Spectacle {R} (You may cast this spell for its spectacle cost rather than its mana cost if an opponent lost life this turn.)
Skewer the Critics deals 3 damage to any target.

Footlight Fiend

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

Kitesail Freebooter

Flying
When Kitesail Freebooter enters the battlefield, target opponent reveals their hand. You choose a noncreature, nonland card from it. Exile that card until Kitesail Freebooter leaves the battlefield.

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.)

Midnight Reaper

Whenever a nontoken creature you control dies, Midnight Reaper deals 1 damage to you and you draw a card.

Fireblade Artist

Haste
At the beginning of your upkeep, you may sacrifice a creature. When you do, Fireblade Artist deals 2 damage to target opponent or planeswalker.

Swamp

Shock

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.

Mountain

Judith, the Scourge Diva

Other creatures you control get +1/+0.
Whenever a nontoken creature you control dies, Judith, the Scourge Diva deals 1 damage to any target.