msem-instigator

Haste
At the beginning of your end step, return Sunwatcher Aspirant to its owner's hand.

As Superset enters, choose two abilities from among flying, first strike, lifelink, prowess, and vigilance.
Each creature you control with exactly one of the chosen abilities has the other chosen ability.

Whenever Supplanter of Realities attacks, proliferate. (You choose any number of permanents and/or players with counters on them, then give each another kind of a counter already there.)
Sacrifice another permanent: Supplanter of Realities gains indestructible until end of turn. Tap it.

You may sacrifice three Treasures rather than pay this spell's mana cost.
Flying, trample, haste

Whenever Supreme Mechanothurge or another artifact you control enters, up to one target artifact you control becomes a copy of another target artifact or creature you control, except it's an artifact in addition to its other types.

Creatures you control get +2/+2 and gain trample until end of turn. If you cast this spell from exile, creatures you control get an additional +2/+2 until end of turn.
Prophecy {2}{G}{G} (Once each turn, you may exile a card with prophecy as you reveal it. When you do, you may cast it for its prophecy cost as long as it's exiled.)

Haste
Ward—Pay 3 life.
Whenever Surface Expeditioneer attacks, if it's embattled, it deals 2 damage to target player or planeswalker. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

As Surge of the Fellors enters, choose Fellor or Lafterii.
• Fellor — Warriors you control have haste.
• Lafterii — Wizard creatures you control have “{2}{R}, {T}: This creature deals 1 damage to target player or planeswalker.”

Search your library for a basic land card and put it onto the battlefield, then shuffle.
Orchestrate {1}{G} (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.)

Whenever a creature you control becomes the target of a spell, that creature gets +3/+3 until end of turn.

Target player draws X cards.

Spells you cast have trial 2. (As you cast them, an opponent of your choice may pay 2 life. If they don't, they fail the trial.)
Whenever an opponent fails a trial of a creature spell, that creature enters with an additional +1/+1 counter on it.
Whenever an opponent fails a trial of a noncreature spell, create a tapped Treasure token.

Haste
{T}, Discard a card: Flip a coin. If you win the flip, draw two cards. Otherwise, you may pay {R}. If you do, repeat this process.

Each other Rogue creature you control enters with an additional +1/+1 counter on it.
Remove a +1/+1 counter from a creature you control: That creature can't be blocked this turn.

Primal {1}{G}{G} (During your turn, you may cast this spell for {1}{G}{G} instead of playing a land.)
When Swampedge Sentinel dies, return another creature card from your graveyard to your hand.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
Create two 1/1 colorless Construct Actor creature tokens.
Creatures you control gain flying until end of turn. Whenever one or more of them deals combat damage to a player this turn, draw a card.
​

At the beginning of each end step, create X 1/1 white Spirit creature tokens with flying, where X is the number of nontoken creatures that died this turn.

Flying
At the beginning of your upkeep, you may pay {1}. If you do, put a +1/+1 counter on Swarm of the Dispossessed.
Sacrifice Swarm of the Dispossessed: Counter target spell with mana value X, where X is the number of +1/+1 counters on Swarm of the Dispossessed.

Swarming Midden enters tapped unless you control a basic Swamp.
{T}: Add {B}.
{1}{B}{B}: Swarming Midden becomes a 2/3 black Rat creature with menace until end of turn. It's still a land. Whenever it attacks this turn, create a 1/1 black Rat creature token with “This creature can't block.”

Choose up to one nonland permanent. Return the rest to their owners' hands.

At the beginning of combat, each player chooses a creature. Those creatures attack or block this turn if able. Whenever one of those creatures dies this turn, Sweep Stakes deals 3 damage to that creature's controller.

Exile target spell or creature. For as long as it remains exiled, its controller may cast that card, and it costs {2} more to cast.

At the beginning of your upkeep, put a charge counter on Swell of Birth, then create a 1/1 colorless Elemental creature token for each charge counter on it.

At the beginning of your end step, put a flood counter on Swelling Sea, then return each nonland permanent with mana value less than or equal to the number of flood counters on Swelling Sea to its owner's hand.

Create two 1/1 red Soldier creature tokens with haste.
Creatures you control get +1/+1 until end of turn.