msem-instigator

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

Deathtouch
When Mire Triton enters, mill two cards and you gain 2 life.

When Miserable Portent enters, create a 1/1 black Harpy creature token with flying.
{3}{B}, Sacrifice Miserable Portent: You draw two cards and you lose 2 life.

Create a 1/1 blue Illusion creature token with “This gets +1/+1 for each other Illusion you control.”
Coalesce {6}{B} (You may cast this from your graveyard for {6}{B}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
Misery Keeps Company is an Illusion in addition to its other types while it's a creature.

Menace
At the beginning of your upkeep, if an opponent has more cards in hand than you, you draw a card and you lose 1 life.

Poisonous 1 (Whenever this creature deals combat damage to a player, that player gets a poison counter. A player with ten or more poison counters loses the game.)
At the beginning of your upkeep, if an opponent is poisoned, you draw a card, you lose 1 life, and you get a poison counter.

Deathtouch
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.)

Reach
At the beginning of your end step, if you've gained 3 or more life this turn, create a 3/3 black Demon Horror creature token and each player loses 3 life.

Monstrous Amalgam gets +X/+X, where X is the number of creature cards in your graveyard.
{B}, Reappropriate: Put a +1/+1 counter on Monstrous Amalgam. Activate only once each turn. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)

Target creature you control gets +1/+0 and gains menace until end of turn. (That creature can only be blocked by two or more creatures.)
Draw a card.

When Monstrous Hunter enters, destroy up to one target creature.
At the beginning of each end step, if a creature died this turn, you draw a card and you lose 1 life.

As an additional cost to cast this spell, sacrifice a token or pay 2 life.
Draw two cards.

({T}: Add {B}.)
Moon of the Encroaching Night enters tapped.
{1}{B}, {T}: Scry 1.

Whenever you gain life, you may put target creature or planeswalker card from your graveyard on top of your library.

{1}{B}, Pay 2 life: Moonlight Butcher gains menace until end of turn.

Return up to two target creature cards from your graveyard to your hand.

Exile target creature or planeswalker, then exile its controller's graveyard.

Target creature gets -2/-2 until end of turn. Mill two cards.

When target creature you control dies this turn, create a token that's a copy of it, except it has no mana cost.

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
{3}: Unlock Mortal's Conundrum. If the revealed card is black, put it into your hand. Otherwise, put it on top of your library.
At the beginning of your upkeep, if Mortal's Conundrum is unlocked, you lose 2 life.

Players can't gain life.
At the beginning of each player's upkeep, if that player has 10 or less life, they lose 1 life.

When Moth-Heart Husk dies, create a 1/1 black Spirit creature token with flying.
Revive {3}{B} ({3}{B}, Exile this card from your graveyard: Create a token that's a copy of this card, except it has no mana cost. Activate this ability only any time you could cast a sorcery.)

Deathtouch
Other creatures you control get -1/-1.
Whenever Mother Night attacks, put target creature card from a graveyard onto the battlefield under your control.

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

Sacrifice a creature or discard a card: Exile the top card of target player's library. You may cast that card for as long as it remains exiled. Any player may activate this ability but only once each turn and only during their turn.
You and permanents you control have hexproof from spells that were exiled with Mr. Jackston or that share a name with a card exiled with Mr. Jackston.