msem-instigator

Concord — You may cast this spell as though it had flash if there are four or more card types among permanents you control.
When Krill-Clan Guardian enters, it fights up to one other target creature. If that creature would die this turn, return it to its owner's hand instead.

Reveal the top four cards of your library. You may put a creature card and/or a land card from among them into your hand. Put the rest into your graveyard, then discard a card if two cards were put into your hand this way.

Forebode three times, then untap each Omen you control. Until end of turn, if you would draw a card while your library has no cards in it, you win the game instead. (Create three tapped colorless Omen artifact tokens with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)

Counter target spell unless its controller pays {4}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Whenever a non-Spirit creature you control dies, you may create a token that's a copy of that creature except the token is a Spirit in addition to its other types and has haste.

Exile all creatures, then for each creature exiled this way, you may return it to the battlefield under its owner's control. For each creature you didn't return to the battlefield this way, its owner may search their library for a basic land card and put it onto the battlefield tapped. Each player that does shuffles.

When Leija's Greenblade enters, you may pay {G}. If you do, destroy target artifact or enchantment.

This spell costs {2} less to cast if you've cast another spell this turn.
Draw two cards, then put a card from your hand on top of your library.

Light the Fuse deals 3 damage to target creature or planeswalker. Whenever a permanent dealt damage by Light the Fuse this turn dies this turn, repeat that process.

Haste
You may cast sorcery and enchantment spells as though they had flash.
Whenever you cast an enchantment, instant, or sorcery spell, Lightning-Fast Lionfish gets +1/+0 and gains first strike until end of turn.

You may have Ligneous Enormity assign its combat damage as though it weren't blocked.
Madness {3}{G}{G} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

When Lionfrill Hunter enters or when you cycle it, put X +1/+1 counters on another target creature you control, where X is the number of cards with a cycling ability in your graveyard.
Cycling {3}{R}{G} ({3}{R}{G}, Discard this card: Draw a card.)

Flying
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.)

Enchant opponent
At the beginning of enchanted player's upkeep, exile up to two target cards from that player's graveyard. If two cards that share a type are exiled this way, you draw a card and you lose 1 life.

When Lost Empire's Legacy enters, create two Treasure tokens.
{1}, {T}, Sacrifice an artifact: Return target artifact card from your graveyard to your hand.

Enchant opponent
When Lost Knowledge enters, enchanted player reveals their hand.
{1}, Sacrifice Lost Knowledge: Scry 2, then draw a card.

When Lunar Vigil enters, draw a card, then scry 2.
If you would draw one or more cards, you may instead put a night counter on Lunar Vigil and draw that many cards minus one.
Sacrifice Lunar Vigil: Target player draws a card and adds {R} for each night counter on it.

When Lurking Angler enters, if seven or more cards are in your graveyard, draw a card. Otherwise, mill two cards.

First mate—Each nonland card in your starting deck is an instant or has flash. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Flash
When Mable enters, you gain 2 life and draw a card.

Flash (You may cast this spell any time you could cast an instant.)
When Majestic Hippocamp enters, target creature gets -2/-0 until end of turn.

Majestic Nauticorn has first strike as long as it's attacking.
Cycling {W} ({W}, Discard this card: Draw a card.)

Put any number of target creature cards from your graveyard on top of your library.
You draw two cards, and you lose 2 life.

Pressure {G} (You may cast this spell for its pressure cost if there are seven or more cards in your graveyard.)
Deathtouch

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.