msem-instigator

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.

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.

Menace
Yaran's Enforcer gets +1/+1 as long as you foretold a card this turn.
Yaran's Enforcer gets +1/+1 as long as you cast a foretold spell this turn.

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.

Flying
Whenever Yawning Crane deals combat damage to an opponent, target tapped creature that player controls doesn't untap during its controller's next untap step.

{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.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
{1}, Sacrifice a creature: Draw a card. Each opponent loses 1 life and you gain 1 life.
Whenever you sacrifice a creature, if you're in a renaissance, each opponent sacrifices a creature. This ability triggers only once each turn.

Inspired — Whenever Yenzu Disciple becomes untapped, each opponent loses 1 life and you gain 1 life.

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.”

Whenever Yenzu Mindwrencher perseveres, each opponent discards a card. (A creature perseveres when it survives damage.)

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

Enchant creature
When Yenzu Puppeteering enters, draw a card.
{1}{U}: Untap enchanted creature.

{4}, {T}, Sacrifice Yenzu Ritual Vessel: Yenzu Ritual Vessel deals 4 damage to target creature or planeswalker.

{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.

Destroy target artifact, enchantment, or planeswalker.
Reconstruct {4}{G}{G} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

Flying, trample
Once during each of your turns, you may cast a spell from your graveyard without paying its mana cost.
When Yhzag, Alpha and Omega is put into a graveyard from anywhere, its owner shuffles their graveyard into their library.

Yi Cang, Thief of Blessings enters 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.)

Flying
When Yielder of Ambition enters, target creature gets +2/+2 until end of turn.
Fleeting {W} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)

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.

Choose three. You may choose the same mode more than once.
• Put a +1/+1 counter on up to one target creature you control, then you may have it fight target creature you don't control.
• Target player creates a 2/2 green Lizard creature token.
• You mill four cards and gain 4 life.

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.