msem-instigator

(Add a quest counter as this enters. Sacrifice after 6.)
Whenever a land you control enters, add a quest counter.
1, 2, 3, 4, 5 — 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.
6 — Until end of turn, creatures you control get +5/+5 and gain vigilance, trample, and haste.
​

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.

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.

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.

[+1]: Exile up to one target tapped creature.
[–2]: Create a 4/4 white Angel creature token with flying.
[–3]: Destroy all creatures. You gain 1 life for each creature destroyed this way.
[–7]: You get an emblem with “At the beginning of each end step, you gain life equal to twice the life you've lost this turn.”

[+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.”)

Deception {2}{U} ({2}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Marilye deals combat damage to a player, you may search your library for an artifact card with mana value less than or equal to that amount of damage, put it onto the battlefield, then shuffle.

Deception {2}{U}{U} ({2}{U}{U}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
As long as it's your turn, Marilye is a 3/2 Elf Rogue creature with hexproof and indestructible.
[+1]: Tap target permanent. It doesn't untap during its controller's next untap step.
[–2]: Exile the top five cards of target opponent's library. You may cast any number of cards exiled this way with total mana value less than or equal to the amount of damage dealt to them this turn without paying their mana costs.

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.

Marin Polgek, Academy Heiress has hexproof as long as you control three or more enchantments.
{1}{W/U}{W/U}: Create a token that's a copy of target enchantment you control.

First mate—Each nonland card in your starting deck has “destroy,” “die,” “graveyard,” and/or “mill” in its printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Deathtouch
When Marisa enters, if it was cast, you may put target permanent card from a graveyard onto the battlefield under your control.

Enchant opponent
Whenever enchanted player searches their library, you may search your library for a card, put it into your hand, then shuffle.

Skip your draw step.
At the beginning of your end step, discard a card. If you do, create a 4/4 white Angel creature token with flying. If you can't, sacrifice Mark of Hubris.

Enchant creature
When enchanted creature dies, you draw three cards and you gain 3 life.

Renown 1
When Marshal Jin Guiying becomes renowned, you may search your library for an artifact or enchantment card, reveal it, put it into your hand, then shuffle.

When Marshcroaker Coaching enters, create three 1/1 blue Frog creature tokens.
Frogs you control have “{T}: Target creature gains flying until end of turn.”

Transcend (Activate as a sorcery to gain the next type and a +1/+1 counter.)
Vigilance
Martoob of Flowing Life has ward {X}, where X is the number of counters on her.
{G}{U}: Angel — Put a +1/+1 counter on each other creature you control.
{2}{G}{U}: Elder — Double the number of counters on permanents you control.

Flying
Whenever you tap a land for mana, add one mana of any type that land produced.
At the beginning of each end step, if you control no untapped lands, transform Martoob, Blessing of Water.

Whenever an attacking creature your team controls dies, you gain 3 life.

Indestructible
Marva of Endless Inspiration can't attack or block unless you've cast a spell with mana value 4 or greater this turn.
At the beginning of your end step, return a card at random from your graveyard to your hand. If it's a land card, return it to the battlefield instead.

[+1]: Discard a card. If you do, draw a card.
[–X]: Marzen deals X damage to you. Exile the top X cards of your library. Until your next turn, you may play those cards.
[–7]: You get an emblem with “If you would draw a card, you may draw three cards instead.”

At the beginning of your upkeep, exile the top card of your library. Masahita, Bloodtongue deals damage to you equal to that card's mana value. Until end of turn, you may play that card.

Lifelink
If you would gain life, you may put that many +1/+1 counters on another creature you control instead.

Creatures your opponents control attack each turn if able.
Blocking creatures you control get +4/+0.
{W}: Untap Masha, Hero of Pelastrov.