msem-instigator

At the beginning of combat on your turn, you may pay {2}{R}{R}. If you do, create a 4/4 red Dragon creature token with flying and haste. Exile that token at end of combat.
Ferocious — Whenever Xiusheng of the Dragon Realm attacks, if you control a creature with power 4 or greater, Xiusheng gains double strike until end of turn.

Menace
Whenever a land enters the battlefield, 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.

Flying
Whenever another creature enters the battlefield under your control, create an Idol token.
Whenever you put a +1/+1 counter on Ya'Ling, put a +1/+1 on each other creature you control. This ability triggers only once each turn.

Other enchantment creatures you control get +1/+1.
As long as you control three or more enchantment creatures, if a triggered ability of an enchantment you control would trigger, that ability triggers an additional time.

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

{T}, Sacrifice another creature: Return target creature card with mana value equal to 1 plus the sacrificed creature's mana value from your graveyard to the battlefield. Activate only as a sorcery.

{1}{G}: Create a 1/1 colorless Construct artifact creature token.
{2}{G}{G}: Target creature you control becomes 4/4. (This lasts indefinitely.)
{4}{G}{G}{G}{G}: Put four +1/+1 counters on each creature you control with power 4 or greater.

Yi Cang, Thief of Blessings enters the battlefield with a +1/+1 counter on them.
{1}: Yi Cang becomes a copy of target creature in their pack, except their name is Yi Cang, Thief of Blessings, they're legendary in addition to their other types, and they have this ability. (Two or more creatures you control with equal power are in a pack.)

Whenever you cast a spell, harmonize twice. (To harmonize, trigger up to one harmony of a permanent you control.)
Harmony — Yita, Almgrove Prodigy gains your choice of flying, first strike, vigilance, lifelink, hexproof, or haste until end of turn.

Vigilance
{X}{G}, {T}: Ylda, the Wild Soul becomes a copy of target creature you control with mana value X, except it has this ability and vigilance. Activate only as a sorcery.

Whenever Yri, the Daring Blade and exactly one other creature attack, Yri and that creature can't be blocked by creatures with mana value 3 or less this turn.

Whenever Yrodu, the Lotus Ablaze attacks, eight target permanents don't untap during their controller's next untap step.
Whenever Yrodu blocks a creature, destroy that creature at end of combat.

Flying, vigilance
If a nonland permanent entering the battlefield would cause a triggered ability of a permanent you control to trigger, you may have that ability trigger an additional time. If you do, each opponent copies that ability and may choose new targets for the copies.

Flying
At the beginning of combat on your turn, choose one —
• Other creatures you control gain flying until end of turn.
• Other creatures you control with flying get +2/+2 until end of turn.

Flying
When Yujei enters the battlefield, create a 1/1 white Bird creature token with flying.
{2}{W}: Put a +1/+1 counter on another target creature. It gains flying until end of turn. If it already has flying, put a +1/+1 counter on Yujei instead.

Whenever you cast a noncreature spell, look at the top X cards of your library, where X is that spell's mana value. Put those cards on top of your library in any order.

Vigilance
Art of war — At the beginning of your end step, if Yuso, Light of Jidai dealt damage to an opponent this turn, you may search your library for a creature card with mana value 2 or less, reveal it, put it into your hand, then shuffle.

Hexproof
{1}{W}{U}, {T}: Exile target creature you control. Return that card to the battlefield under its owner's control at the beginning of the next end step.

Flying
Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
Whenever Zaidha, Seraph of Calamity deals combat damage to a player, choose up to two target nonland permanents that player controls and target nonland permanent you control. Destroy one of those permanents at random.

Whenever Zana, the Dreamer attacks, you may pay {3}{R}{R}. If you do, for each attacking nontoken creature you control, create a tapped and attacking token that's a copy of it, except the tokens aren't legendary. Exile those tokens at the beginning of the end step.

First strike
Whenever Zankon, Ema's Claws blocks or becomes blocked, put a +1/+1 counter on each creature you control.

This spell costs {1} less to cast for each creature that died this turn.
At the beginning of your upkeep, put target creature card from a graveyard onto the battlefield under your control.
{1}, Sacrifice another creature: Zarad, the Final Adversary gains indestructible until end of turn.

{1}{R}, {T}, Sacrifice a land: Create a colorless Desert land token with “{T}: Add {C}.”
{1}{R}, {T}, Sacrifice a Desert: Destroy up to two target lands.

When Zareen, the Second Shah enters the battlefield, search your library for a creature card with mana value 2 or less or a planeswalker card, reveal it, put it into your hand, then shuffle.
Monument {2}{W}{W} (You may cast this transformed from your graveyard for its monument cost. Exile it if it would leave the battlefield or not resolve.)

Flying
Whenever you attack with three or more creatures, exile the top card of your library. You may play that card until you exile another card with Zarthane, Scourge of Galdurheim.
{2}{B/R}: Target creature gets +1/+0 and gains menace until end of turn. Activate only as a sorcery.