msem-instigator

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever an opponent loses 3 or more life, add a quest counter.
1 — Destroy up to one target creature with power or toughness 2 or less.
2 — Create Sir Jasper Reborn, a legendary 3/1 black Zombie Mouse Knight creature token with menace.
3 — Search your library for a card, reveal it, put it into your hand, then shuffle. If you revealed a card named Karoa's Downfall this way, you may cast it without paying its mana cost.

Double the power and toughness of target creature you control until end of turn. It doesn't untap during its controller's next untap step.

Return target creature card from your graveyard to your hand.
Augmented — If you've spent {W}{U}{B}{R}{G} to cast spells this turn, return it to the battlefield instead.

When Thespian's Page enters, return target instant or sorcery card from your graveyard to your hand.

Vanguard — Whenever a creature you control attacks alone, you may put a charge counter on Expert Belt and attach it to that creature.
Equipped creature has hexproof.
Equipped creature gets +1/+0 for each charge counter on Expert Belt.
Equip {2}

As long as this creature isn't a Zombie, it and other Knights and Soldiers you control get +1/+1 and have vigilance. Otherwise, it and other Zombies you control get +1/+1 and have menace.
Arise {1}{W}{B} ({1}{W}{B}, Exile this from your graveyard as a sorcery: Create a black token copy of it that's also a Zombie and can't block.)

{3}, Sacrifice another artifact: Put two +1/+1 counters on Foundryborn Ingester.
When Foundryborn Ingester dies, you may exile it. If you do, return target artifact card from your graveyard to your hand.

Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
Menagerie — If there are five or more creature types among creatures you control, creatures you control get +1/+1 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.

At the beginning of each opponent's upkeep, exile Daril's Timewalker and up to one other target nonland permanent you control, then return those cards to the battlefield under their owner's control.

Flash
Flying
{U}, Sacrifice this creature: Counter target noncreature spell unless its controller pays {2}.

When Wistful Fox enters, reveal the top eight cards of your library. You may put a creature card from among them into your hand. Put the rest on the bottom of your library in a random order.

You may cast a spell with mana value X or less from your hand without paying its mana cost, where X is the number of lands you control.

Trample
When Ghastly Progenitor enters, each opponent reveals their hand. Choose two nonland cards revealed this way. Their owners discard those cards.

Enchant creature
Enchanted creature has first strike and trample.

(Transform this if it's not attached to a creature.)
Enchant creature you control
The Scourgebone Pact's rider gets +2/+1, has flying, lifelink and deathtouch, and can't dismount. (This still transforms into a creature if its rider leaves the battlefield.)

Flying, lifelink
Improve {1}{W/B} ({1}{W/B}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
Once each turn, when you gain life, you may have each opponent lose 2 life.

Target creature gets +3/+3 and gains haste until end of turn.

When Deathless Hunter dies, you may put it on the bottom of its owner's library.

Flash
When Aethermancer's Familiar enters, at the beginning of the next end step, you may aetherize target creature you control. (To aetherize, create a token that's a copy of it, then exile that token.)

Enchant creature
Enchanted creature gets +2/+2 and has “Whenever this creature deals combat damage to a player, return up to one target creature card from your graveyard to your hand.”

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you cast a noncreature spell, add a quest counter.
1, 2 — Draw a card, then discard a card.
3 — Return up to two target instant and/or sorcery cards from your graveyard to your hand.
​

Converge — Destroy up to X target artifacts or enchantments, where X is the number of colors of mana spent to cast Bury the Past.

Other creatures you control get +0/+1.
Bulwark — {W}: Target creature gains lifelink until end of turn. Activate only if you control a creature with toughness 4 or greater.

Whenever you cast a spell, if mana from an artifact was spent to cast it, exile the top card of your library. You may play that card until you exile another card with Savant of Cables.