msem-instigator

When Dominator's Diadem enters, you gain 3 life.
{2}{W}, {T}: Tap target creature.

Return target creature or land card from your graveyard to your hand.

Exile the top two cards of your library. Until the end of your next turn, you may play one of those cards, or both if this spell was foretold.
Foretell {R} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Whenever you cast a spell from anywhere other than your hand, put a +1/+1 counter on Ruthless Advisor.
Surpass {5}{B} ({5}{B}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Target creature gets +2/+2 and gains trample until end of turn.

This spell costs {2} less to cast if you control a creature with power 4 or greater.
Bonk deals 4 damage to any target.

Enchant creature
Enchanted creature has double strike.
Mirage {1}{W} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

When GenTech Architect enters, create a Function token with “Put two +1/+1 counters on a creature you control.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

When Long Lost Cause enters, each opponent exiles a card from their hand or a creature they control.

Vanishing 3 (This permanent enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Whenever a time counter is removed from Thespian's Finale, create a token that's a copy of target creature. Sacrifice that token at the beginning of your next upkeep.

Flying, menace, haste
Twisted Archangel has indestructible as long as an opponent has four or more cards in hand.

Target opponent reveals their hand. You choose a card from it. Exile that card. If a land card is exiled this way, its owner may conjure a card named Plains, Island, Swamp, Mountain, or Forest on top of their library.

Swarm of Sporemites gets +1/+1 for each creature card and Revelation card in your graveyard.

{T}: Add {C}.
{9}, {T}, Exile Whiterun Gates: Take an extra turn after this one.

Mill five cards, then for each of those cards, a creature you control salvages that card unless an opponent pays 3 life. (Exile it from your graveyard until that creature leaves the battlefield. Whenever that creature deals combat damage to a player, put a card it salvaged into your hand.)

You gain 3 life. Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Destroy target creature with flying.

Wither (This deals damage to creatures in the form of -1/-1 counters.)
Abyssal Accuser must be blocked if able.

Counter target spell that targets you or a permanent you control.
Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

Nonbasic landwalk (This creature can't be blocked as long as defending player controls a nonbasic land.)
Art of war — At the beginning of your end step, if Kenshiro's Cavalry dealt damage to an opponent this turn, put a +1/+1 counter on it.

Flying
Whenever Phantasmal Owl attacks, it gets +1/+1 until end of turn for each other creature you control with flying.

Whenever a noncreature permanent enters, Petaldiver deals 1 damage to that permanent's controller.

[+1]: Tanya, the Mooncursed becomes a legendary 3/1 red Werewolf creature with first strike until end of turn.
[–2]: Tanya, the Mooncursed deals 3 damage to target creature or planeswalker.
[–4]: Destroy target nonbasic colorless permanent.

Deploy 3 (As this enters, you may tap any number of other creatures you control with total power 3 or more.)
When Relief Battalion enters deployed, draw a card.

Whenever you cast a spell with • in its text, you may pay {2} any number of times. For each time you do, copy that spell. You may reselect modes and choose new targets for the copy.
{2}, Sacrifice Palaisun, Maktali's Opus: Draw a card.

Whenever a creature enters under an opponent's control, draw a card unless that player pays {1}.