msem-instigator

Each player sacrifices a creature. (Then exile this card. You may cast the artifact later from exile.)

Destroy target creature or planeswalker you don't control. Its controller creates two tapped Treasure tokens.

{2}, Sacrifice another creature: Create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Deathtouch

Return all creature cards from your graveyard to the battlefield, then exile all but one of them.

Once each turn, when you search your library, you may add {B}{B}.

Create a 1/1 black and red Vampire creature token with menace. If this spell was cast from a graveyard, create two of those tokens instead.
Flashback {3}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Whenever a creature dealt damage by Truth Extractor this turn dies, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Enchant player
At the beginning of enchanted player's upkeep, they choose one —
• That player reveals their hand and discards a card.
• That player discards a card at random.

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Enchanted creature gets +1/+0 and has deathtouch. (Any amount of damage it deals to a creature is enough to destroy it.)

Menace
Whenever an opponent discards a card, monstrosity 2. (If this creature isn't monstrous, put two +1/+1 counters on it and it becomes monstrous.)

Choose one —
• Return target creature card from your graveyard to your hand.
• Pay {4}. If you do, return target creature card from your graveyard to the battlefield.

Exile target creature. Its controller may profit. (To profit, create a colorless Gold artifact token with “Sacrifice this artifact: Add one mana of any color.”)

Flying, lifelink
Sacrifice a creature: Until end of turn, Turned Watcher gets +1/+0 and gains “Whenever Turned Watcher deals combat damage to a player, draw a card.”

Choose X. You may choose the same mode more than once.
• Each opponent loses 3 life and you gain 3 life.
• Each opponent sacrifices a nonland permanent and you create a Treasure token.
• Each opponent discards a card and you draw a card.

As an additional cost to cast this spell, exile X cards from your graveyard.
You draw X cards and you lose X life.
Coalesce {8}{B} (You may cast this from your graveyard for {8}{B}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

When Twice-Lived Dead dies, create a 2/2 black Zombie creature token.

Destroy target creature with power or toughness 2 or less.

Whenever a creature you control dies, Twilight Blade deals 1 damage to each opponent and you gain 1 life.

Whenever Twilight Dancer attacks, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Each player loses 1 life and mills a card.

Target player loses 1 life. Scry 1.
Fabled {2}{B} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that player.)

Target player loses 3 life and you gain 3 life. (Then exile this card. You may cast the creature later from exile.)

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
{1}{B}, Sacrifice a creature: Put a +1/+1 counter on Twisted Cultist.

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)
Revive {1}{B} ({1}{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.)

Target creature gets +3/+3 and gains winnow until end of turn. (Damage dealt to it also causes its controller to lose that much life.)