msem-instigator

Whenever a nontoken creature you control enters, you may scry 1. (To scry 1, look at the top card of your library. You may put that card on the bottom of your library.)

Draw two cards.
Memento {5}{U}{U} (You may cast this from your graveyard for {5}{U}{U}. If you do, put it onto the battlefield transformed after it resolves. Exile it if it would leave the battlefield or not resolve.)

{T}, Sacrifice Worldshaper Adept: Choose two basic land types. Create a tapped colorless land token of the chosen types.

Vigilance
Whenever a creature you control survives damage, it explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then you may put that card in your graveyard.)

Colossal 2—{4}{B}{B} (You may cast this for its colossal cost to have it enter with two +1/+1 counters; or pay {4}{B}{B} as a sorcery: Put two +1/+1 counters on it if it has none.)
Menace
When Wretched Catoblepas's colossal ability puts one or more counters on it, each opponent sacrifices a creature.

I, II — Draw a card.
Discovery — Noncreature spells you cast cost {1} less to cast.

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever two or more creatures you control deal combat damage to a player, add a quest counter.
Create a 2/1 black and red Cat Pirate creature token with menace.
Create a colorless artifact token named Motherlode with “{T}: Add two mana of any one color” and
“{3}, {T}, Discard your hand: Draw two cards.”

Choose one —
• Copy target instant, sorcery, or Equipment spell you control. You may choose new targets for the copy.
• Create a token that's a copy of target Equipment you control.

Whenever you cast an instant or sorcery spell, you may have Xenocrata's Fleet become a 4/4 Ship artifact creature with haste until end of turn.
Whenever Xenocrata's Fleet deals combat damage to an opponent, create that many 1/1 red Warrior creature tokens.

You may play an additional land each turn.
Whenever a player plays a land, that player draws a card.

(Choose only one work as a sorcery to add its ability.)
When Xie'e Amphitheatre enters, search your library for a card and exile it face down, then shuffle. You may cast that card on any turn you sacrificed a permanent.
{B}: Intro: Together
At the beginning of your upkeep, you lose 1 life and create a 0/1 black Cultist creature token with “{1}{B}{B}, Sacrifice three Cultists: Create a 5/5 black Demon creature token.”
{2}{B}: Finale: Alone
Whenever a Demon you control enters, each opponent loses life equal to its power and you gain that much life.

[+1]: You may sacrifice a creature. If you do, return a creature card with lesser mana value from your graveyard to the battlefield.
[–1]: Other creatures and planeswalkers you control gain indestructible and can't have counters removed from them until your next turn.
[–X]: Exile X target cards from graveyards. Xiong Mao deals X damage to any target.

Choose one or both—
• Target creature you control gets +2/+2 until end of turn.
• Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Archive 5 (As this enters, shuffle the top five cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Recursive — Xirix's Study has all nonrecursive abilities of all Study cards in graveyards except for their archive abilities.

Whenever you cast a legendary spell, create a 1/1 white Human creature token.
{W}{U}{B}{R}{G}: Search your library for a legendary card, reveal it, put it into your hand, then shuffle. The next legendary spell you cast this turn costs {W}{U}{B}{R}{G} less to cast.

Menace
Whenever a land enters, you may search its controller's library for up to three land cards with the same name as that card, put them into that player's graveyard, then that player shuffles.

When Yamisaran Bladedancer enters, you may attach an Equipment you control to target creature you control.

When Yamisaran Guard enters, create a colorless Equipment artifact token with “Equipped creature gets +1/+1” and equip {1}.

Reach
{T}: Yangzhi Cloudpiercer deals 1 damage to target player or planeswalker.

Foretell {1}{U}{U} (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.)
Counter target spell. If this spell was foretold, draw a card.

Foretell {2}{U}{U} (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.)
Choose one. If this spell was foretold, you may choose both instead —
• Draw three cards, then discard two cards.
• The owner of target nonland permanent puts it on the top or bottom of their library.

{2}, Exile a land card from your graveyard: Create a token that's a copy of that land.

Siempre que ganes vidas, los Clérigos que controlas obtienen +1/+1 y ganan la habilidad de arrollar hasta el final del turno.

Demon spells you cast cost {2} less to cast and an additional 2 life to cast.
Whenever you cast a Demon spell, create a 0/1 black Cultist creature token with “{1}{B}{B}, Sacrifice three Cultists: Create a 5/5 black Demon creature token.”

Deathtouch
Inspired — Whenever Yenzu Nightblade becomes untapped, target creature you control gets +1/+1 and gains deathtouch until end of turn.