msem-instigator

{T}: Add {C}.
{1}{C}{C}, {T}: Return target legendary creature to its owner's hand.

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.)
Other artifacts you control have extort.
Whenever a spell you control resolves, if it was extorted three or more times, each opponent discards a card and you draw a card.

{T}: Add {C}.
{1}, {T}, Return Collapsing Ground to its owner's hand: Add one mana of any color.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever a marked creature dies, you lose 1 life and you draw a card.

Investigate, then counter target spell unless its controller pays {1} for each Clue you control. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Whenever Coral Hunter attacks, another target creature can't be blocked this turn.

[+2]: Put two +1/+1 counters or loyalty counters on up to one other target creature or planeswalker.
[0]: Cornrose, the Mighty deals 3 damage to target creature. That creature deals damage equal to its power to Cornrose.
[–2]: Until end of turn, target creature gets +X/+X and gains trample, where X is its power.

Return target creature or planeswalker card from your graveyard to the battlefield. If that card was a creature, it's an Actor in addition to its other types.

Crumbling Vestige enters tapped.
When Crumbling Vestige enters, add one mana of any color.
{T}: Add {C}.

When Crux Pinnacle enters, for each color, exile up to one target permanent of that color until Crux Pinnacle leaves the battlefield.
Whenever a player casts a spell, if there are five or more spells on the stack, you win the game.

Whenever you sacrifice a permanent, scry 1.
{1}, Sacrifice a nonland permanent: You gain 1 life.

Crystal Garden enters tapped.
{T}: Add one mana of any color. You can't spend this mana to cast a creature spell.

Menace, deathtouch
Whenever a creature an opponent controls dies, that player loses 2 life and you gain 2 life.

Whenever a creature enters this turn, destroy it.

Whenever Daring Skythief crews a Vehicle, that Vehicle gains flying until end of turn.

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

Target creature gets +2/+2 and gains flying and lifelink until end of turn.
Orchestrate {W} (You may exile this card from your hand anytime you could cast a sorcery for its orchestrate cost. When you next resolve a spell, you may cast this from exile without paying its mana cost.)

({T}: Add {R}.)
Derelict Amphitheatre enters tapped.
{R}, {T}, Reveal a red card from your hand: Scry 1.

Desert Temple enters tapped.
As Desert Temple enters, an opponent of your choice chooses Oasis or Desiccation.
• Oasis — {T}: Add one mana of any color.
• Desiccation — {T}: Add {C}{C}. You lose 1 life.

When Diasune Irregular enters, if you control another Warrior, draw a card.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever a marked creature dies, Diasune Tracker deals 1 damage to target player.

Other Warriors you control get +1/+1.
Whenever one or more Warriors you control deal combat damage to a player, untap all lands you control.

Hexproof

Whenever Distracting Performer becomes tapped, you may tap target creature.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
You can't lose the game and your opponents can't win the game.
I — Your life total becomes 1.
II — Double your life total.
III — Create an X/X white Avatar creature token with indestructible, where X is your life total.