msem-instigator

{W}{U}, {T}: Target creature gets +2/+2 and gains flying until end of turn.
{U}{B}, {T}: Target player mills three cards.
{B}{R}, {T}: Monolith of Ages deals 3 damage to any target.
{R}{G}, {T}: Target creature gets +4/+2 and gains trample until end of turn.
{G}{W}, {T}: Populate. (Create a token that's a copy of a creature token you control.)

{5}, {T}, Exile a creature you control: Exile target creature.

Whenever a creature you control enters, put a devotion counter on Monument of the Masses.
At the beginning of your upkeep, if Monument of the Masses has thirty-five or more devotion counters on it, you win the game.

Monumental Siege deals 5 damage divided as you choose among any number of targets. Whenever a creature dealt damage this way this turn dies, 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.”)

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

Moonlight Stag has vigilance as long as it has a +1/+1 counter on it.

Look at target player's hand and the top card of that player's library. Look at the top four cards of your library, then put them back in any order.

Flying
Whenever another creature you control attacks, you may pay {1}. If you do, put a +1/+1 counter on it.

{T}: Add {W}.
{W}, {T}: Target creature gains vigilance until end of turn.

Whenever a creature you control enters, you gain 1 life.
{2}{U}: Return target creature you control to its owner's hand.

Choose target creature. Scry 3, then reveal the top card of your library. You gain X life and put X +1/+1 counters on that creature, where X is the revealed card's mana value.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast a noncreature spell, each opponent loses life equal to Morose Harpist's power.

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.

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

({T}: Add {B} or {G}.)
Mossy Shrine enters tapped unless you control two or more basic lands.

Flying
Whenever another creature you control enters, you gain 1 life.

Flying
When Mother of Owls dies, you may return target creature an opponent controls to its owner's hand.

Creatures you control get +2/+2 and gain first strike until end of turn.

First strike, haste
When Mounted Marksman enters, it deals 2 damage to target creature you don't control.

Scry 2, then reveal the top or bottom card of your library. Creatures you control get +X/+X until end of turn, where X is that card's mana value.
Draw a card.

When Mul Daya Elder enters, search your library for a basic land card, put it onto the battlefield tapped, then shuffle.
Whenever a land you control enters, put a +1/+1 counter on Mul Daya Elder.

Exile a nonland card from your graveyard: For each colored mana symbol in that card's mana cost, add one mana of that color. Activate only once each turn. (For example, if the card's mana cost is {3}{G}{G}{W}, you add {G}{G}{W}.)

When Mulchborn Behemoth enters, you may sacrifice any number of lands.
Mulchborn Behemoth gets +1/+1 for each land card in your graveyard.
{B}{G}, Sacrifice a land: Destroy target creature or land.

Look at the top three cards of your library, then put them into your graveyard or back on top of your library in any order.
Draw two cards.

As an additional cost to cast this spell, exile a creature card from your graveyard.
Create a tapped 2/3 black Mummy creature token.