msem-instigator

Enchant creature
When Mantle of the Returned enters the battlefield, return target creature card from your graveyard to the battlefield. It's a Zombie in addition to its other types.
Enchanted creature gets +1/+1 for each Zombie you control.

Target creature you control gets +1/+0 until end of turn. It fights up to one target creature you don't control. (Each deals damage equal to its power to the other.)

Colossal 4—{5}{U}{U}{U} (You may cast this for its colossal cost to have it enter with four +1/+1 counters; or pay {5}{U}{U}{U} as a sorcery: Put four +1/+1 counters on it if it has none.)
Whenever Megalokraken enters the battlefield or attacks, reveal the top X cards of your library, where X is Megalokraken's power. You may cast a noncreature spell with mana value X or less from among them without paying its mana cost. Put the rest on the bottom of your library in a random order.

Meletian Trireme can't be blocked by creatures with power 2 or less.
Whenever Meletian Trireme enters the battlefield or deals combat damage to a player or planeswalker, scry 1, then draw a card.
Crew 2 (Tap any number of creatures you control with total power 2 or greater: This Vehicle becomes an artifact creature until end of turn.)

When Meletis Oracle enters the battlefield, scry 1, then draw a card.

Heroic — Whenever you cast a spell that targets Meletis Stargazer, scry 2.
{T}: Look at the top card of your library. If it's a permanent card with mana value 3 or less, you may reveal it and put it into your hand.

Flash
Flying
When Meletis Stratomancer enters the battlefield, target creature an opponent controls gets -2/-0 until end of turn.

When Memento Gorgon enters the battlefield, mill X cards, where X is your devotion to black. Then return a card milled this way to your hand. You lose 1 life. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

This spell can't be countered.
Whenever Meren, Bane of the Cairns attacks, exile target creature card from your graveyard. You may cast that card for as long as it remains exiled by sacrificing a creature in addition to paying its other costs.

Counter target spell unless its controller pays {2}. If that spell targets you or a permanent you control, counter that spell instead.

Embellish {4}{W} (If you cast this spell for {4}{W}, create a 1/1 blue Thopter artifact creature token with flying when it enters the battlefield.)
When Meticulous Mechanist enters the battlefield, scry 1.

Enchant creature you control
When Military Authority enters the battlefield, create two 1/1 white Soldier creature tokens.
Enchanted creature gets +2/+2.

Colossal 3—{6}{R} (You may cast this for its colossal cost to have it enter with three +1/+1 counters; or pay {6}{R} as a sorcery: Put three +1/+1 counters on it if it has none.)

Menace
When Minotaur Skullsmasher enters the battlefield, choose a nonland card type. Then target opponent reveals their hand. You choose a card of the chosen type from it. That player discards that card.

Heroic — Whenever you cast a spell that targets Mira and Kalisti of Akros, copy that spell. You may choose new targets for the copy. (The copy isn't cast. A copy of an Aura spell becomes a token.)

Deathtouch
When Mire Triton enters the battlefield, mill two cards and you gain 2 life.

When Miserable Portent enters, create a 1/1 black Harpy creature token with flying.
{3}{B}, Sacrifice Miserable Portent: You draw two cards and you lose 2 life.

Counter target noncreature spell with an odd mana value. (Zero is even.)

Hexproof
Mist-Valley Ancient enters the battlefield tapped.
Cycling {2} ({2}, Discard this card: Draw a card.)

{1}{R}, Discard a card: Draw a card. Mist-Valley Minotaurs gets +2/+0 until end of turn.

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.

Molten Mire enters the battlefield tapped unless you control a basic land.
{T}: Add {B} or {R}.

Target creature gets +2/+2 until end of turn. You gain 2 life.

Exile target creature. That creature's controller reveals cards from the top of their library until they reveal a creature card. That player puts that card onto the battlefield, then shuffles the rest into their library. If you own that card, it enters the battlefield with an additional X +1/+1 counters on it, where X is its power.

Flying
When Morningheart Griffin dies, return target enchantment card from your graveyard to your hand.