msem-instigator

Gestalt (When this or another creature enters under your control, you may merge it with the one in play, keeping counters and attachments. They become the permanent on top plus all abilities from under it.)
This creature can't be blocked by creatures with power 1 or less.

Haste
{T}, Sacrifice a creature: Ashspeaker deals 1 damage to any target.

Whenever Aspect of An'yama attacks, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
Spells you cast from your graveyard, activated abilities of cards in your graveyard, and reprise costs of spells you cast cost {1} less.

Menace (This creature can't be blocked except by two or more creatures.)
Whenever a creature you control deals combat damage to a player, you may have Aspect of Rage deal 1 damage to any target.

Aspiring Dragon has flying and haste as long as you control another Dragon.
{2}{R}{R}: Aspiring Dragon gets +3/+0 until end of turn.

Equipped creature gets +1/+0 and has deathtouch and “{T}: This creature deals 1 damage to target creature you don't control. Sacrifice Assassin's Shuriken.”
Equip {2}

Create three 1/1 colorless Construct Actor creature tokens.

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.

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.

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.

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.

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.

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

Vanishing 4 (This permanent enters with four time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
Equipped creature gets +3/+3.
Equip {2}

Put a +1/+1 counter on target attacking creature.
Draw a card.

When Atlas of Worlds enters, search your library for any number of land cards with different names and exile them, then shuffle.
You may play lands exiled with Atlas of Worlds.

Prevent all combat damage that would be dealt this turn.
Create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

When you discard Attack Vector, you may cast it from your graveyard.
Exile the top two cards of your library. Until the end of your next turn, you may play one of those cards.

When Attuned Ancient enters, if you control a legendary creature, you may have Attuned Ancient deal damage equal to its power to target creature an opponent controls.

Rhapsody {4}{R}{R} (Pay {4}{R}{R} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
Trample
Whenever Attuned Slayer deals combat damage to a player, exile that many cards from the top of your library. You may play those cards this turn.

You may put a +1/+1 counter on target creature you control. It deals damage equal to its power to another target creature or planeswalker.

{1}, Sacrifice a creature or enchantment: Exile the top card of your library. You may play that card this turn.