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.

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.

Manaforge Cinder

{1}: Add {B} or {R}. Activate no more than three times each turn.

Blazing Hellhound

{1}, Sacrifice another creature: Blazing Hellhound deals 1 damage to any target.

Greven, Predator Captain

Menace
Greven, Predator Captain gets +X/+0, where X is the amount of life you've lost this turn.
Whenever Greven attacks, you may sacrifice another creature. If you do, you draw cards equal to that creature's power and you lose life equal to that creature's toughness.

Azra Oddsmaker

At the beginning of combat on your turn, you may discard a card. If you do, choose a creature. Whenever that creature deals combat damage to a player this turn, you draw two cards.

Anathemancer

When Anathemancer enters, it deals damage to target player equal to the number of nonbasic lands that player controls.
Unearth {5}{B}{R} ({5}{B}{R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Mayhem Devil

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

Boris Devilboon

{2}{B}{R}, {T}: Create a 1/1 black and red Demon creature token named Minor Demon.

Anje Falkenrath

Haste
{T}, Discard a card: Draw a card.
Whenever you discard a card, if it has madness, untap Anje Falkenrath.

Falkenrath Aristocrat

Flying, haste
Sacrifice a creature: Falkenrath Aristocrat gains indestructible until end of turn. If the sacrificed creature was a Human, put a +1/+1 counter on Falkenrath Aristocrat.

Marsh Goblins

Swampwalk (This creature can't be blocked as long as defending player controls a Swamp.)

Gobhobbler Rats

Hellbent — As long as you have no cards in hand, Gobhobbler Rats gets +1/+0 and has "{B}: Regenerate Gobhobbler Rats." (The next time it would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Munitions Expert

Flash
When Munitions Expert enters, you may have it deal damage to target creature or planeswalker equal to the number of Goblins you control.

Demigod of Revenge

When you cast this spell, return all cards named Demigod of Revenge from your graveyard to the battlefield.
Flying, haste

Bedevil

Destroy target artifact, creature, or planeswalker.

Cryptborn Horror

Trample
Cryptborn Horror enters with X +1/+1 counters on it, where X is the total life lost by your opponents this turn.

Blood Cultist

{T}: Blood Cultist deals 1 damage to target creature.
Whenever a creature dealt damage by Blood Cultist this turn dies, put a +1/+1 counter on Blood Cultist.

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.

Goblin Bombardment

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

Cinder Shade

{B}: Cinder Shade gets +1/+1 until end of turn.
{R}, Sacrifice Cinder Shade: It deals damage equal to its power to target creature.

Dire Fleet Captain

Whenever Dire Fleet Captain attacks, it gets +1/+1 until end of turn for each other attacking Pirate.

Fulminator Mage

Sacrifice Fulminator Mage: Destroy target nonbasic land.

Kulrath Knight

Flying
Wither (This deals damage to creatures in the form of -1/-1 counters.)
Creatures your opponents control with counters on them can't attack or block.

Footlight Fiend

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

Emberstrike Duo

Whenever you cast a black spell, Emberstrike Duo gets +1/+1 until end of turn.
Whenever you cast a red spell, Emberstrike Duo gains first strike until end of turn.

Cult Guildmage

{3}{B}, {T}: Target player discards a card. Activate only as a sorcery.
{R}, {T}: Cult Guildmage deals 1 damage to target opponent or planeswalker.

Goblin Outlander

Lyzolda, the Blood Witch

{2}, Sacrifice a creature: Lyzolda, the Blood Witch deals 2 damage to any target if the sacrificed creature was red. Draw a card if the sacrificed creature was black.

Chainer, Nightmare Adept

Discard a card: You may cast a creature spell from your graveyard this turn. Activate only once each turn.
Whenever a nontoken creature you control enters, if you didn't cast it from your hand, it gains haste until your next turn.

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.

Acidic Sliver

All Slivers have "{2}, Sacrifice this permanent: This permanent deals 2 damage to any target."

Elite Headhunter

Menace (This creature can't be blocked except by two or more creatures.)
{B/R}{B/R}{B/R}, Sacrifice another creature or an artifact: Elite Headhunter deals 2 damage to target creature or planeswalker.

Mogis, God of Slaughter

Indestructible
As long as your devotion to black and red is less than seven, Mogis isn't a creature.
At the beginning of each opponent's upkeep, Mogis deals 2 damage to that player unless they sacrifice a creature of their choice.