Rain of Gore

If a spell or ability would cause its controller to gain life, that player loses that much life instead.

Tymaret, the Murder King

{1}{R}, Sacrifice another creature: Tymaret, the Murder King deals 2 damage to target player or planeswalker.
{1}{B}, Sacrifice a creature: Return Tymaret from your graveyard to your hand.

Infernal Tutor

Reveal a card from your hand. Search your library for a card with the same name as that card, reveal it, put it into your hand, then shuffle.
Hellbent — If you have no cards in hand, instead search your library for a card, put it into your hand, then shuffle.

Titan Hunter

At the beginning of each player's end step, if no creatures died this turn, Titan Hunter deals 4 damage to that player.
{1}{B}, Sacrifice a creature: You gain 4 life.

Anthem of Rakdos

Whenever a creature you control attacks, it gets +2/+0 until end of turn and Anthem of Rakdos deals 1 damage to you.
Hellbent — As long as you have no cards in hand, if a source you control would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

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.

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Pain Magnification

Whenever an opponent is dealt 3 or more damage by a single source, that player discards a card.

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.