Rampaging Ferocidon

Menace
Players can't gain life.
Whenever another creature enters, Rampaging Ferocidon deals 1 damage to that creature's controller.

Flame Fusillade

Until end of turn, permanents you control gain "{T}: This permanent deals 1 damage to any target."

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.

Niv-Mizzet, the Firemind

Flying
Whenever you draw a card, Niv-Mizzet, the Firemind deals 1 damage to any target.
{T}: Draw a card.

Kederekt Parasite

Whenever an opponent draws a card, if you control a red permanent, you may have Kederekt Parasite deal 1 damage to that player.

Burn Down the House

Choose one —
• Burn Down the House deals 5 damage to each creature and each planeswalker.
• Create three 1/1 red Devil creature tokens with "When this creature dies, it deals 1 damage to any target." They gain haste until end of turn.

Zariel, Archduke of Avernus

+1: Creatures you control get +1/+0 and gain haste until end of turn.
0: Create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."
−6: You get an emblem with "At the end of the first combat phase on your turn, untap target creature you control. After this phase, there is an additional combat phase."

Garna, Bloodfist of Keld

Whenever another creature you control dies, draw a card if it was attacking. Otherwise, Garna deals 1 damage to each opponent.

Dance with Devils

Create two 1/1 red Devil creature tokens. They have "When this creature dies, it deals 1 damage to any target."

Nekusar, the Mindrazer

At the beginning of each player's draw step, that player draws an additional card.
Whenever an opponent draws a card, Nekusar, the Mindrazer deals 1 damage to that player.

Fate Unraveler

Whenever an opponent draws a card, Fate Unraveler deals 1 damage to that player.

Ob Nixilis, Captive Kingpin

Flying, trample
Whenever one or more opponents each lose exactly 1 life, put a +1/+1 counter on Ob Nixilis, Captive Kingpin. Exile the top card of your library. Until your next end step, you may play that card.

Ghyrson Starn, Kelermorph

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Three Autostubs — Whenever another source you control deals exactly 1 damage to a permanent or player, Ghyrson Starn, Kelermorph deals 2 damage to that permanent or player.

Goblin Bombardment

Sacrifice a creature: Goblin Bombardment deals 1 damage to any target.

Blasting Station

{T}, Sacrifice a creature: Blasting Station deals 1 damage to any target.
Whenever a creature enters, you may untap Blasting Station.

Rakdos Charm

Choose one —
• Exile target player's graveyard.
• Destroy target artifact.
• Each creature deals 1 damage to its controller.

Maestros Diabolist

Deathtouch, haste
Whenever Maestros Diabolist attacks, if you don't control a Devil token, create a tapped and attacking 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."

Ob Nixilis, the Adversary

Casualty X. The copy isn't legendary and has starting loyalty X. (As you cast this spell, you may sacrifice a creature with power X. When you do, copy this spell. The copy becomes a token.)
+1: Each opponent loses 2 life unless they discard a card. If you control a Demon or Devil, you gain 2 life.
−2: Create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."
−7: Target player draws seven cards and loses 7 life.

Aether Sting

Whenever an opponent casts a creature spell, Aether Sting deals 1 damage to that player.

Devils' Playground

Create four 1/1 red Devil creature tokens. They have "When this creature dies, it deals 1 damage to any target."

Impact Tremors

Whenever a creature you control enters, this enchantment deals 1 damage to each opponent.

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad, the Grim deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Raphael, Fiendish Savior

Flying
Other Demons, Devils, Imps, and Tieflings you control get +1/+1 and have lifelink.
At the beginning of each end step, if a creature card was put into your graveyard from anywhere this turn, create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."

Mayhem Devil

Whenever a player sacrifices a permanent, Mayhem Devil deals 1 damage to any target.

Make Mischief

Make Mischief deals 1 damage to any target. Create a 1/1 red Devil creature token. It has "When this creature dies, it deals 1 damage to any target."

Heat of Battle

Whenever a creature blocks, Heat of Battle deals 1 damage to that creature's controller.

Burning Earth

Whenever a player taps a nonbasic land for mana, Burning Earth deals 1 damage to that player.

Zurzoth, Chaos Rider

Whenever an opponent draws their first card each turn, if it's not their turn, you create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."
Whenever one or more Devils you control attack one or more players, you and those players each draw a card, then discard a card at random.

Creeping Bloodsucker

At the beginning of your upkeep, Creeping Bloodsucker deals 1 damage to each opponent. You gain life equal to the damage dealt this way.

Hellrider

Haste
Whenever a creature you control attacks, Hellrider deals 1 damage to the player or planeswalker it's attacking.

Deathbringer Thoctar

Whenever another creature dies, you may put a +1/+1 counter on Deathbringer Thoctar.
Remove a +1/+1 counter from Deathbringer Thoctar: It deals 1 damage to any target.

Tibalt, Rakish Instigator

Your opponents can't gain life.
−2: Create a 1/1 red Devil creature token with "When this creature dies, it deals 1 damage to any target."