msem-instigator

Exile up to one target artifact or enchantment.
Coalesce {5}{G} (You may cast this from your graveyard for {5}{G}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

When Ursagore enters, you gain 4 life. Then if it was foreshadowed, create a 3/3 green Bear Spirit creature token.
When Ursagore dies, draw a card.
Foreshadow {5}{G}{G} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

When Chapel Defendant enters, you gain 1 life for each Citizen you control.

Abandoned Shores enters tapped if you control another nonbasic land.
{T}: Add {G} or {U}.

Move all counters from target creature onto another target creature.

War-Pride Champion can't be blocked by creatures with power 2 or less.
Stampede — Whenever War-Pride Champion and a creature with greater power attack, target creature you control gets +2/+2 until end of turn.

Reach
{T}: Sadistic Sparkmage deals 1 damage to each opponent.

Cleansing Brimstone deals 2 damage to any target. If a creature or planeswalker dealt damage this way would die this turn, exile it instead.

You may play lands from your graveyard.
Whenever a land you control enters, create a 1/1 white Peasant creature token.

Counter target spell unless its controller pays {2}.
Wanderlust — If that spell has mana value 2 or less and you control four or more differently named lands, counter that spell.

Harmony — Search your library for a basic land or Desert card, reveal it, and put it into your hand. Then shuffle.
When Trumpeting Pathmaker enters, harmonize. (Trigger up to one harmony of a permanent you control.)

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
{3}: Unlock Mortal's Conundrum. If the revealed card is black, put it into your hand. Otherwise, put it on top of your library.
At the beginning of your upkeep, if Mortal's Conundrum is unlocked, you lose 2 life.

Advance {2} (Cast this for {2} to advance it as it enters. {2}: Advance this as a sorcery.)
Equipped creature gets +1/+1 for each artifact you control.
Equipped creature must be blocked by an additional creature for each time it and this artifact have advanced this turn to be blocked.
Equip {3}

Lionize {G} ({G}, Exile this card from your hand: Put a +1/+1 counter on target creature and it gains the following abilities until end of turn. You may cast this card on a later turn from exile.)
Vigilance, reach

Once each turn, when a player casts a spell, you may choose two target players. Each of those players exiles cards from the top of their library until they exile a nonland card with mana value less than that spell's. They may cast those cards without paying their mana cost. Then they put the rest of the exiled cards on the bottom of their library in a random order. (The active player puts their spell on the stack first.)

Flourishing Plains enters tapped.
As Flourishing Plains enters, choose a basic land type.
Flourishing Plains is the chosen type in addition to its other types.

Enchant artifact or creature
When Embed enters, tap enchanted permanent.
Enchanted permanent doesn't untap during its controller's untap step.

Target player reveals their hand. You choose a nonland card from it. That player discards that card.

Gain control of target creature until end of turn. Untap that creature. Until end of turn, it gains haste and “Whenever this creature deals combat damage to a player, aetherize it.” (To aetherize, create a token that's a copy of it, then exile that token.)

Eureka! (At the beginning of each end step, you get a research counter if you cast a spell this turn. Then if you have eight or more research counters, remove them and create a Masterpiece token of your choice.)
Whenever an artifact you control enters, up to two target creatures get +1/+0 and haste until end of turn.

Whenever Bourasan Street Watch attacks, you may pay {W}. If you do, Bourasan Street Watch gains indestructible until end of turn.

Menace
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Menace
Lonesome Trio can't attack or block unless at least three other creatures you control also attack or block.

{2}, {T}, Sacrifice Old Map: Search your library for a basic land card, put it onto the battlefield, then shuffle.

Flying
When Spectre of Terror deals combat damage to a player, that player discards a card.
Madness {1}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)