msem-instigator

Deception {B} ({B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Lifelink
{1}{B}: Nimunotian Shadow gets +1/+1 until end of turn.

Post a bounty on target creature you don't control, then each opponent sacrifices a creature. (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.)

Pressure—Reappropriate black. (You may cast this spell by exiling two black cards from your hand and/or graveyard if there are seven or more cards in your graveyard.)
Destroy target creature or planeswalker.

Menace
Crew 3
You may exile two creature cards from your graveyard rather than pay Phantom Walker's crew cost.

When Pilgrim of Bal enters, you may search your library and/or graveyard for an Aurashaper or Curse card, reveal it, and put it into your hand. If you searched your library, shuffle.

Menace
Sabotage — Whenever an opponent or permanent an opponent controls becomes the target of a spell you control, each opponent discards a card.

Rotrider Renegade can't block or be blocked.
{1}{B}: Rotrider Renegade gets +1/+1 until end of turn.
Dash—Reveal a Rogue card from your hand, Pay 2 life (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)

When Saffrisa's Darkcaster enters, look at the top four cards of your library. You may substantiate a card from among them. Put the rest into your graveyard. (To substantiate a card, put it onto the battlefield face down as a 2/2 creature. You may turn it face up and cast it at any time for its mana cost if it isn't a creature.)

Lifelink
Once each turn, when you draw a card, you may reveal it and a card you own from outside the game with a different name and the same mana cost. If you do, exile the first card and put the second into your hand. (Mana costs must be identical.)

Deathtouch
Whenever Scaleblight Bokor attacks, it gets +1/+1 until end of turn for each Curse attached to defending player.

Mill five cards, then you may exile any number of cards from your graveyard. Create an X/X black Horror creature token with menace, where X is the number of cards exiled in this way. (To mill five cards, put five cards from the top of your library into your graveyard.)

Return target creature card from your graveyard to the battlefield.
Reconstruct {4}{B}{B}{B} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

This spell costs {1} less to cast for each poison counter your opponents have.
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 end step, each opponent with seven or more poison counters loses the game.

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you attack, add a quest counter.
Mill a card, then create a 1/1 black Peasant creature token.
Each player sacrifices a creature.
Monument {2}{B}{B} (You may cast this transformed from your graveyard for its monument cost. Exile it if it would leave the battlefield or not resolve.)

Equipped creature gets +X/+X, where X is the number of cards in your graveyard.
Sacrifice a creature other than equipped creature: Equipped creature gains lifelink and indestructible until end of turn.
Equip {3}

Mimic—Discard a card (Discard a card as a sorcery: This takes the shape of your choice.) [1/1]
[Shape 1] Menace
Soulshifter gets +1/+1 for each creature card in your graveyard. [1/1]
[Shape 2] Deathtouch
Whenever Soulshifter deals combat damage to a player, you may return target creature card from your graveyard to your hand. [2/2]

Menace
Whenever you cast a cryptic spell, you may return target creature card from your graveyard to your hand. (Artifacts, enchantments and modal spells are cryptic.)

Whenever one or more cards leave your graveyard for the first time each turn, create a 3/2 green Crocodile creature token with trample.

First mate — Each nonland card in your starting deck is an artifact, a Pirate, or has “artifact,” “Treasure,” or “Pirate” in its printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Whenever Tinbeard of the Brine attacks, each opponent loses X life and you gain X life, where X is the number of artifacts you control plus the number of Pirates you control.

Bleed {1}{B} (You may cast this spell for its bleed cost if an opponent lost life this turn.)
Deathtouch
Treacherous Informant enters with two +1/+1 counters on it if you paid its bleed cost.
You may cast spells for their bleed costs if you lost life this turn.

Bleed {1}{B} (You may cast this spell for its bleed cost if an opponent lost life this turn.)
When Undermurk Scavenger enters, you draw a card and you lose 1 life.

Glitch—Sacrifice a creature. (Remove one [restriction] for each time you pay the glitch cost.)
When Unshackled Revolutionary enters, you may destroy target creature an opponent controls [with mana value 3 or less]. [You lose 3 life.]

Reprise {3}{B} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)
This spell deals 2 damage to target creature. You gain life equal to the total damage dealt by this spell.

Voidtouched Nightblade can't block.
Simulacrum (When this creature dies, exile it from your graveyard. If you do, create a token that is a copy of it except it is a colorless 1/1 Crystal Elf Rogue artifact creature.)

Harmony — Warriors you control get +1/+0 and gain menace until end of turn.
Whenever Aleud Warcaller attacks, harmonize. (Trigger up to one harmony of a permanent you control.)