msem-instigator

When Abura-no-Oni enters the battlefield, target player mills two cards.

Creatures you don't control get -1/-1.
Mirage {1}{B} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

When Arisen Haploc enters the battlefield, return target creature card from a graveyard to its owner's hand.
Revive {5}{B}{B} ({5}{B}{B}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Destroy target face-up creature.

When Blightbringer enters the battlefield, creatures your opponents control get -1/-1 until end of turn.
Unearth {3}{B} ({3}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)

Bloodleaf Butcher gets +1/+0 and has deathtouch as long as five or more cards are in your graveyard.

Exile up to six land cards from your graveyard. For each card exiled this way, create a 1/1 black Spirit creature token with flying.
Flashback {1}{B}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

As an additional cost to cast this spell, pay 1 life.
Departed Evangel can't block.
You may cast Departed Evangel from your graveyard if a creature died this turn.

{1}{B}, Mill three cards: Return Dredging Aberration from your graveyard to your hand.

When Driver of Hordes enters the battlefield, create a tapped 2/2 black Zombie creature token.
Unearth {3}{B} ({3}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)

Whenever you gain life, target opponent loses that much life.
{T}, Pay 3 life: Flip a coin. If you win the flip, you gain 6 life.

Each player sacrifices a creature. Create a tapped 2/2 black Zombie creature token.

All creatures get -2/-2 until end of turn.

When Graygulch Turncoat enters the battlefield, you may post a bounty on target creature. If you do, each opponent loses life equal to the number of bounty counters on creatures. (Put a bounty counter on that creature. It has “When this creature dies, each opponent draws a card” as long as it has a bounty counter on it.)

{2}{B}, Sacrifice a creature: Manifest the bottom card of your library. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)
Whenever a creature you control is turned face up, it gains deathtouch until end of turn.

When Infested Goblin dies, choose target creature. At the beginning of your next upkeep, that creature's controller sacrifices it.

Flying
When Kai'Dwo, Eternal Ravager enters the battlefield, create seven Idol tokens. (They're artifacts with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
Whenever you sacrifice an Idol, each opponent sacrifices a creature.

When Kiyomi's Disciple enters the battlefield, put target creature card from a graveyard onto the battlefield under your control. When Kiyomi's Disciple is no longer on the battlefield, that creature's controller sacrifices it.

Whenever you gain life for the first time each turn, each opponent loses 2 life.

Whenever a creature dies, scry 1 and each opponent loses 1 life.

Flying, deathtouch
Whenever an opponent loses life for the first time each turn, that player loses 1 life and you gain 1 life.

Whenever a creature dies, put a +1/+1 counter on Mother's Disciples.

Deception {B} ({B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
When Oshiruko Operative enters the battlefield, target player loses 1 life.

You draw two cards, lose 2 life, and mill two cards.

Sacrifice a creature: Rapacious Demon gets +1/+1 and gains flying until end of turn. Activate only as a sorcery.