msem-instigator

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever a marked creature dies, put a +1/+1 counter on Mei's Collector.

Flying
When Mei's Understudy enters, if you control another Actor, draw a card.

[+1]: Draw a card unless an opponent discards a card.
[–3]: Gain control of target creature until the end of your next turn.
[–6]: Choose up to four cards in graveyards. You may play those cards without paying their mana costs.

{T}: Add {C}.
{T}, Exile Memorial of the Fallen: Shuffle your graveyard into your library.

Whenever Merfolk Vandal deals combat damage to a player, you may pay {U}. If you do, transform it.

Creatures with power greater than the number of cards in their controller's hand can't attack.

Whenever equipped creature blocks or becomes blocked by a creature, you may have equipped creature become a copy of that creature until end of turn.
Equip {1}

Counter target spell.

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever Mistress of Frost extorts a spell, you may tap target artifact or creature.

At the beginning of your upkeep, you may choose one —
• Put a card from your hand on the bottom of your library. If you do, draw a card.
• Discard a card. If you do, put the bottom card of your library into your hand.

Flying
When Moonlit Charmer enters, tap target artifact or creature. It doesn't untap during its controller's next untap step.

{T}: Add {C}.
{T}, Exile two cards from your graveyard: Add {U} or {B}.

Prowess, trample
When this creature transforms into Mortal Frame, add {R}{R}{R}.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Each player discards a card or sacrifices a creature.
III — Each opponent loses life equal to the number of creature cards in their graveyard. You gain life equal to the number of creature cards in your graveyard.

When Ol' Sycamore enters, choose up to two —
• Ol' Sycamore fights another target legendary creature.
• Destroy target noncreature storied permanent. (Enchantments and legendary permanents are storied.)

Whenever Oracle of Flames becomes tapped, up to one target creature you control gets +2/-2 until end of turn.

Flash
Oscanthor, Trader's Ruin can't be blocked.
Whenever a creature you control deals combat damage to a player, draw a card.

Counter target spell if you have more cards in hand than its controller.

{T}: Add {C}.
{7}, {T}: Copy target instant or sorcery spell with {X} in its mana cost. You may choose new targets for the copy. This ability costs {1} less to activate for each instant and sorcery card in your graveyard.

{T}, Sacrifice Palace of Reflections: Choose a land you control. Search your library for a land card with the same name as the chosen land, put it onto the battlefield tapped, then shuffle.

Whenever Passionate Painter becomes untapped, you may discard a card. If you do, draw a card, then transform Passionate Painter.

{U}, {T}: Sacrifice any number of nontoken creatures. Create an X/X blue Horror creature token, where X is the total power of those creatures. Then if X is 4 or greater, you may transform Performer of Brilliance.

{2}, {T}: You gain life equal to the number of colors among cards in your graveyard.
{W}{U}{B}{R}{G}: Transform Performer of Enlightenment.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Target opponent mills three cards.
III — You may cast target nonland card from a graveyard this turn and you may spend blue mana as though it were mana of any color to cast it.

Target creature gets -2/-2 and is marked until end of turn.