msem-instigator

Menace
Ni'Ama's Emissary gets +1/+1 as long as you control a red or white permanent.

This spell costs {2} less to cast if an opponent lost life this turn.
Destroy target creature.

When Night Howlers enters, target opponent reveals three cards from their hand and you choose one of them. Exile that card until Night Howlers leaves the battlefield.

Enchant player
At the beginning of enchanted player's end step, they lose 2 life unless they discard a card.

Flying (This creature can't be blocked except by creatures with flying or reach.)
{B}: Night Screecher gains deathtouch until end of turn. (Any amount of damage this deals to a creature is enough to destroy it.)

Target player loses X life and you gain X life, where X is the number of permanents you control with counters on them.

At the beginning of your upkeep, if there are no noncreature cards in your graveyard, you may return target creature card from your graveyard to the battlefield.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Each player discards a card or sacrifices a creature.
III — Each opponent loses life equal to the number of creature cards in their graveyard. You gain life equal to the number of creature cards in your graveyard.

Flying
Whenever an opponent discards a card, put a +1/+1 counter on Nightbane Specter.
Whenever Nightbane Specter deals combat damage to a player, that player discards a card.

Until end of turn, target creature gains deathtouch and “When this creature dies, return it to the battlefield tapped under its owner's control.”

Flying (This creature can't be blocked except by creatures with flying or reach.)
As long as Nightclad Stalker is enchanted, it gets +1/+0 and has deathtouch and lifelink.

Sacrifice a creature: Look at the top card of target player's library. You may have that player put that card into their graveyard.

Deception {1}{B} ({1}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Nightfall Infiltrator deals combat damage to a player, that player discards a card.

Destroy target creature. Recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)

Whenever a storied permanent you control enters, each opponent discards a card. (Enchantments and legendary permanents are storied.)

Pressure—{B}, Pay 5 life. (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Create an X/X black Horror creature token, where X is the number of cards in your graveyard.

Create a token that's a copy of target creature card in your graveyard, except it has no mana cost.

{B}, Discard a card: Post a bounty on target 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.)

Whenever a creature dies, its controller loses 1 life.

Nightshaper's Domain enters tapped.
{T}: Add {B}.

Whenever a creature attacks one of your opponents, that player loses 1 life.

Choose X. Target player reveals their hand and discards all nonland cards with mana value X.

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.

Whenever an opponent discards a card, exile it. You may cast that card as long for as it remains exiled, and you may spend black mana as though it were mana of any color to cast that spell.

(Transcend as a sorcery to gain that type and a +1/+1 counter.)
When Niu Mo Wang enters, you may have all players sacrifice a nontoken creature, enchantment, or planeswalker.
{B}: Demigod — Each player discards a card.
{X}{B}: God — Return any number of target creature cards not named Niu Mo Wang, Ashen Absolution with different mana values X or less from your graveyard to the battlefield. X can't be 0.