msem-instigator

{T}: Discard two cards. If you do, draw two cards.

Menace, haste
Whenever Manic River-Fishers attacks, you may search defending player's library for an instant or sorcery card that shares a name with a card in their graveyard and cast it without paying its mana cost. That player shuffles.

Glitch—Pay 3 life. (Remove one [restriction] for each time you pay the glitch cost.)
Create a 6/6 black Demon artifact creature token with flying, trample, [“This creature can't attack players with 10 or more life,”] [and “This creature can't block creatures with power 4 or less.”]

Manifest a creature card at random from your graveyard. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Add {R} and two mana of any one color.
When you next cast a spell this turn, Manifest Irrationality deals 3 damage to any target.

Flying
Whenever you attack, create two 1/1 white Human creature tokens that are tapped and attacking. Creatures you control get +1/+1 until end of turn.
Fleeting {2}{W}{W} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)
Whenever Manipulator of Waves attacks, mill three cards. Then create a 0/0 blue Elemental Serpent creature token with “This creature gets +1/+1 for each five cards in your graveyard.”

Frenzy 1 (Whenever this creature attacks and isn't blocked, it gets +1/+0 until end of turn.)

Enchant creature
When Mantle of the Returned enters, 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.

(Add a quest counter as this enters. Sacrifice after 6.)
Whenever a land you control enters, add a quest counter.
Reveal the top card of your library. If it's a land card, put it into your hand. Otherwise, you may put it into your graveyard.
Until end of turn, creatures you control get +5/+5 and gain vigilance, trample, and haste.
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This spell costs {1} less to cast for each differently named creature you control.
Whenever a creature you control enters, if it has a different name than each other creature you control and card in your graveyard, draw a card.

When Marauder's Broadsword enters, you may pay {1}. If you do, create a 1/1 white Soldier creature token and attach Marauder's Broadsword to it.
Equipped creature gets +2/+0.
Equip {2}

Civilized — When Marble Row Healer enters, if you control an artifact, a creature, and an enchantment, you gain 4 life.

Choose X. You may choose the same mode more than once. Create a creature token for each of the chosen characteristics.
• 1/1 white Bird with flying.
• 1/3 blue Turtle.
• 1/1 black Chipmunk with lifelink.
• 1/1 red Rabbit with haste.
• 2/1 green Squirrel with reach.

Enchant creature
Enchanted creature gets +1/+1.
When enchanted creature dies, return another target creature card from your graveyard to your hand.

Flying, lifelink
Your opponents can't search libraries.
{B}, Pay 2 life, Discard a card: Search your library for a card, then shuffle and put that card on top.

Improve {1}{W} ({1}{W}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
Prevent all combat damage that would be dealt to attacking embattled creatures you control. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Double strike
Improve {1}{R/W} ({1}{R/W}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
At the beginning of combat on your turn, if you control three or more embattled creatures, you may search your library for an artifact, enchantment, or Angel card, reveal it, put it into your hand, then shuffle.

Target creature's controller judges it. Then if they honored it, you gain control of that creature until end of turn. Untap it. It gains haste until end of turn. (That creature's controller honors it by putting a +1/+1 counter on it or condemns it by sacrificing it to draw a card.)

[+1]: Discard a card. If you did, draw a card.
[–2]: Create a Bullet token. Until end of turn, if a Bullet you control would deal damage, it deals that much damage plus 1 instead. (It’s an artifact with “{T}, Sacrifice this artifact: It deals 1 damage to any target.”)

You may spend mana as if it was mana of any color to cast cards exiled with Marilye.
[+1]: Exile the top card of each opponent's library. Until end of turn, you may cast spells from among those exiled cards.
[–3]: Exile target creature. You may cast that card. If you don't, return it to its owner's hand.
[–7]: Gain control of up to five target nonland permanents.

Whenever Marine Delver attacks, draw a card.

{X}{U}{U}: Marine Monster can't be blocked by creatures with mana value X or less this turn.

Marinton Occultist can't block or be blocked.
Whenever one or more cards are put into a player's graveyard from their library, Marinton Occultist gets +1/+1 until end of turn.

When Marionette Phantom enters, choose one —
• Draw a card.
• Proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)