msem-instigator

Target player sacrifices an attacking creature.
Bulwark — That player sacrifices two attacking creatures instead if you control a creature with toughness 4 or greater.

Create three 1/1 colorless Construct Actor creature tokens.

This spell costs {1} less to cast for each legendary creature you control.
Search your library for a legendary creature card with mana value X or less, put that card onto the battlefield, then shuffle.

Target creature gets -5/-0 until end of turn. Adjudicate. (Create a white Aura enchantment token with enchant creature and “Sacrifice this token: Untap enchanted creature” attached to target creature.)

Exile target nonland permanent. For each of its colors, its controller creates a 1/1 colorless Spirit creature token.

Menace
Once during each of your turns, when you sacrifice a permanent, you may put a +1/+1 counter on Assimilated Runner.

When Assurance of Finality enters, you may discard a card. If you do, draw two cards.
{1}, Sacrifice Assurance of Finality: Creatures you control gain haste until end of turn.

At the beginning of your upkeep, if the number of permanents you control, the number of cards in your hand, and the number of cards in your graveyard are all equal, you win the game.

First strike
Chronicle (As this enters and after your draw step, add a lore counter. Stop after III.)
[Lore I-II] Put a +1/+1 counter on each of up to two other target creatures you control.
[Lore III] Remove all lore counters from Astral Capricine. Create two 0/1 white Goat creature tokens.

Menace
Chronicle (As this enters and after your draw step, add a lore counter. Stop after III.)
[Lore I-II] Exile the top card of your library. You may play that card this turn.
[Lore III] Remove all lore counters from
Astral Cerberus. It deals 3 damage to up to one target creature.

Whenever you cast a spell, put a charge counter on Astral Dynamo.
{T}, Remove any number of charge counters from Astral Dynamo: Add that much {C}.

If a nontoken creature you control would die, you may exile it instead. If you do, create two 1/1 white Spirit creature tokens with flying.

Deathtouch
Chronicle (As this enters and after your draw step, add a lore counter. Stop after III.)
[Lore I-II] You may sacrifice another creature. If you do, draw a card.
[Lore III] Remove all lore counters from Astral Leech. Each opponent sacrifices a creature.

Trample
Chronicle (As this enters and after your draw step, add a lore counter. Stop after III.)
[Lore I-II] Creatures you control gain vigilance until end of turn.
[Lore III] Remove all lore counters from Astral Leucrocota. You gain 4 life.

Flying
Chronicle (As this enters and after your draw step, add a lore counter. Stop after III.)
[Lore I-II] Draw a card, then discard a card.
[Lore III] Remove all lore counters from Astral Man-o'-War. Return up to one target creature you don't control to its owner's hand.

Ward—Exile three cards from your graveyard. (Whenever this permanent becomes the target of a spell or ability an opponent controls, counter it unless that player exiles three cards from their graveyard.)
Menagerie — Astralhorn Familiar gets +2/+2 as long as there are five or more creature types among creatures you control.

When Astrid, Disgruntled Princess enters, destroy target creature with mana value less than or equal to the number of Warriors you control.

Whenever equipped creature attacks, put a progress counter on Astrina, Tempered by Glory.
Equip {1}
[PROGRESS 1-2] Equipped creature gets +1/+1 and has first strike.
[PROGRESS 3+] Equipped creature gets +4/+4 and has first strike and lifelink.

Archive 3 (As this enters, shuffle the top three cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Whenever you draw a card from the archived library, put the top card of your main library on the bottom of the archived library.
{R}: Exchange a card from the archived library with a card from your hand.

When Astute Prophet enters, draw a card. If you control a legendary creature, draw two cards instead.

When Astute Sceneweaver enters, proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Whenever a non-Spirit creature deals combat damage to a player, destroy that creature. Its controller creates a 1/1 colorless Spirit creature token.

Once each turn, when Atal, the Shroudmaker enters or you attack with one or more Horrors, you may create two tapped 1/1 colorless Human creature tokens. If Atal isn't a token, creatures you control gain flying until end of turn.
{2}{W}{W}, Discard Atal: Create a token that's a copy of Atal, the Shroudmaker, except it's 4/4 and isn't legendary. Activate only as a sorcery.

Whenever a nonbasic land becomes tapped or enters tapped, it doesn't untap during its controller's untap steps for as long as Ataraxia remains on the battlefield.

Whenever a land you control enters, you may pay {2}{G}. If you do, put a +1/+1 counter on Atdrik Ravager.