msem-instigator

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.

Flying, haste
Miyoga Firebird attacks each combat if able.
Whenever you cast your third instant or sorcery spell this turn, you may return Miyoga Firebird from your graveyard to the battlefield.

Flying, haste
Miyoga Flameweaver can't block.
Whenever Miyoga Flameweaver attacks, exile the top card of your library. You may play that card until end of turn.

(Transcend as a sorcery to gain that type and a +1/+1 counter.)
Flying
{2}{U}{U}: Wizard
Draw a card, then discard a card. Mizuki gains “Noncreature spells you cast cost {1} less.”
{6}{U}{U}: Avatar
Draw two cards. Mizuki gains “Whenever Mizuki attacks, you may cast a noncreature spell from your hand without paying its mana cost.”

Indestructible
As long as your devotion to black and red is less than seven, Mogis isn't a creature.
At the beginning of your upkeep, each player discards a card. Then you draw a card. If an opponent can't discard a card or discarded a land card, you create a 2/3 red Minotaur creature token.

Flash
When Mokuteki Ambusher enters, until end of turn, other creatures you control gain “{T}: This creature deals 1 damage to any target.”

When Monastery Scribe enters, return target instant or sorcery card from your graveyard to your hand.

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.)

When Monk of Mid-Autumn enters, choose one —
• Put a double strike counter on Monk of Mid-Autumn.
• Destroy target artifact or enchantment.
• Monk of Mid-Autumn deals 2 damage to target tapped creature and you gain 2 life.

First strike

Whenever Moon-Scarred Tuzi attacks, target creature in its pack gains first strike until end of turn. (Two or more creatures you control with equal power are in a pack.)

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

Moonlight Curator has flying as long as it's embattled. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

First strike
Other Harpies you control get +1/+1 and have first strike.
Whenever a Harpy you control dies, put a +1/+1 counter on Moonlight Stalker.

Once each turn, when another nontoken creature is returned to your hand from the battlefield, you may create a token that's a copy of that creature.

Whenever Morbid Mimic enters or attacks, exile up to one target creature card from a graveyard.
Morbid Mimic has all activated abilities of cards exiled with it.

When Morose Bohemian enters, scry 1, then draw a card.

Prowess, trample
When this creature transforms into Mortal Frame, add {R}{R}{R}.

Gain control of target creature until end of turn.
Coalesce {6}{U}{B} (You may cast this from your graveyard for {6}{U}{B}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
As long as Mortal Whims Falter is on the battlefield, you can't lose control of permanents.

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.

Flying
{1}{W/U}{W/U}: Creatures you control gain flying until end of turn if another creature you control has flying. The same is true for first strike, double strike, deathtouch, haste, indestructible, lifelink, menace, reach, trample, and vigilance.

Mossvine Lurker has trample as long as it has a +1/+1 counter on it.

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.)

Whenever you sacrifice a permanent, you may put a -1/-1 counter on target creature.