Fetid Imp

Flying
{B}: This creature gains deathtouch until end of turn. (Any amount of damage it deals to a creature is enough to destroy it.)

Sower of Discord

Flying
As this creature enters, choose two players.
Whenever damage is dealt to one of the chosen players, the other chosen player also loses that much life.

Demon of Death's Gate

You may pay 6 life and sacrifice three black creatures rather than pay this spell's mana cost.
Flying, trample

Touch of Moonglove

Target creature you control gets +1/+0 and gains deathtouch until end of turn. Whenever a creature dealt damage by that creature dies this turn, its controller loses 2 life. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Reaper from the Abyss

Flying
Morbid — At the beginning of each end step, if a creature died this turn, destroy target non-Demon creature.

Defile

Target creature gets -1/-1 until end of turn for each Swamp you control.

Soot Imp

Flying
Whenever a player casts a nonblack spell, that player loses 1 life.

Jet Medallion

Black spells you cast cost {1} less to cast.

Pilfering Imp

Flying
{1}{B}, {T}, Sacrifice this creature: Target opponent reveals their hand. You choose a nonland card from it. That player discards that card. Activate only as a sorcery.

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature of their choice.

Imp's Mischief

Change the target of target spell with a single target. You lose life equal to that spell's mana value.

Echoing Return

Return target creature card and all other cards with the same name as that card from your graveyard to your hand.

Swamp

Infernal Sovereign

Flying, trample
Skip your draw step.
Whenever you play a land or cast a spell, you draw a card and you lose 1 life.

Indulgent Tormentor

Flying
At the beginning of your upkeep, draw a card unless target opponent sacrifices a creature of their choice or pays 3 life.