msem-instigator

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 enters the battlefield under your control, you may pay {2}{G}. If you do, put a +1/+1 counter on Atdrik Ravager.

Vanishing 4 (This permanent enters the battlefield 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 the battlefield, 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 the battlefield, 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.

You may put a creature card from your hand onto the battlefield. That creature gains haste until end of turn. Sacrifice that creature at the beginning of the next end step unless you pay its mana cost reduced by up to {3}{R}{R}.

Augury Hydra enters the battlefield with X +1/+1 counters on it.
When Augury Hydra enters the battlefield, scry Y, where Y is its power, then draw Y cards.

Menace, haste
At the beginning of combat on your turn, gain control of up to two target noncreature, nonland permanents your opponents control until end of turn. Untap those permanents. You may attach any number of Equipment among them to creatures you control until end of turn. (They unattach at end of turn.)

Whenever Aukashi, Electric Legacy enters the battlefield or equipped creature dies, attach Aukashi to a creature you control.
Whenever equipped creature deals damage to a permanent or player, Aukashi deals 2 damage to that permanent or player.
Equipped creature has double strike as long as a creature you controlled died this turn.
Equip {2}

Whenever equipped creature deals combat damage to a player, exile an instant or sorcery card from your graveyard. Then copy any number of cards exiled with Aukashi, the Rising Storm with mana value X or less and cast the copies without paying their mana costs, where X is the number of cards exiled with Aukashi.
Equip {2}

When Aureate Golem enters the battlefield, create a Treasure token. Each other player creates a tapped Treasure token. (They're artifacts with “{T}, Sacrifice this artifact: Add one mana of any color.”)

{1}, {T}, Sacrifice Aureate Panorama: Search your library for a land card that could produce each color of mana, put it onto the battlefield, then shuffle.

This spell can't be countered.
Hexproof

Menace
Whenever Auros, Flame-Cursed attacks, it deals 3 damage to each opponent.

This spell can't be countered.
When Auros enters the battlefield, it deals damage to any target equal to your devotion to red. (Each {R} in the mana costs of permanents you control counts toward your devotion to red.)
{R}, Sacrifice Auros, Discard your hand: Draw three cards.

Trample
Auspicious Qilin must be blocked if able.

Whenever you play a land, return a card at random from your graveyard to your hand.
Whenever you cast a green spell, reveal the top card of your library. If it's a land card, put it into your hand. Otherwise, mill it.