msem-instigator

Chronicle (As this enters and after your draw step, add a lore counter. Stop after III.)
[Lore I-II] Each player loses 1 life.
[Lore III] Create a 1/1 black Harpy creature token with flying.

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.

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

Whenever Nightly Herald attacks, it deals damage to the defending player equal to the number of Wolves and Werewolves you control.

Flash
Flying
Whenever a player discards a card, you draw a card. This ability triggers only once each turn.

{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.)

Reach, deathtouch
When Nightshade Ambusher enters, you may pay {1}{G}. When you do, destroy target creature with flying.

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.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Nizev Brawler enters, target creature can't block this turn.

When Njel Crocodile enters, you may have it fight target creature. (Each deals damage equal to its power to the other.)

Whenever No-Good Gunpointer attacks, you may pay 3 life. If you do, draw a card.

Wither (This deals damage to creatures in the form of -1/-1 counters.)
{1}{B}: Return Noonfiend from your graveyard to your hand.

As long as it's not your turn, Northrime Amalgam gets -2/+2.

Flying
Whenever Notorious Windraider attacks, other attacking Pirates and Rogues you control gain flying until end of turn.

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
At the beginning of your end step, if an opponent is cursed, surveil 2.

Prowess
Whenever you cast a noncreature spell, Noxan Pilgrim gains lifelink until end of turn.

Motivate 1 (When this creature enters, you may motivate target creature with less power than this by putting a +1/+1 counter on it.)
When Nroxi Beastmaster motivates a creature, that creature gains trample until end of turn.

Flying
Whenever you cast a creature spell for the first time each turn, create a 1/1 green Insect creature token.

Trample
When Oakcudgel Giant enters, you may destroy target artifact or enchantment.

Defender, first strike
{1}{G}: Oaken Spearman can attack this turn as though it didn't have defender.

When Obscure Apostle enters, 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.”)
Whenever you sacrifice an Idol, Obscure Apostle can't be blocked this turn.

Flash
Whenever you cast an artifact or enchantment spell, put a +1/+1 counter on Observer of Secret Paths. It can't be blocked this turn.

Flash
Ocean's Edge Kraken enters with a hexproof counter on it.
{6}{U}{U}, Remove a hexproof counter from Ocean's Edge Kraken: Return all other creatures to their owners' hands.

Whenever you cast a spell, note its colors.
At the beginning of combat on your turn, up to X target creatures get +2/+0 and gain menace until end of turn, where X is the number of colors noted with Off-Set Rumormonger.