msem-instigator

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.

When Young Chasqui enters, if you cast it, reveal the top five cards of your library. Put any number of creatures named Young Chasqui from among them into your hand. Put the rest of the revealed cards on the bottom of your library in a random order.
A deck can have any number of cards named Young Chasqui.

Whenever a nontoken creature you control dies, create a 1/1 black Skeleton creature token.

Double strike, haste

You have hexproof.
Adorned — Youthful Savior has hexproof as long as it's equipped and/or enchanted.

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, 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.

[+1]: Up to one target creature gets +1/+1 and gains first strike until your next turn.
[+1]: Choose a player or planeswalker other than Yuno Moonchaser. Creatures can't attack that player or planeswalker until your next turn.
[0]: Move any number of loyalty counters from Yuno onto target planeswalker.

Double the number of each kind of counter on any number of target permanents.

Archive 2 (As this enters, shuffle the top two 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, target creature you control gains vigilance and indestructible until end of turn.

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.

Equipped creature gets +2/+2 and has poisonous 2. (Whenever this creature deals combat damage to a player, that player gets two poison counters.)
Whenever equipped creature attacks, create a 1/1 green Snake creature token with poisonous 1 that's tapped and attacking. Exile that token at end of combat.
Equip {2}

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.

Other creatures you control get +3/+0.
When Zare enters, create a 2/1 white Bird creature token with flying and a 3/3 green Horse creature token.
Whenever another creature you control attacks or blocks, sacrifice it at end of combat.

Zareen's Pariah is all colors.
Flying
During each of your turns, you may cast a spell of each color from your graveyard.

When Zareen, the Second Shah enters, 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.)