msem-instigator

Enchant opponent
Whenever Substack Exploit or another Curse becomes attached to enchanted player, that player loses 1 life and you gain 1 life.

Breach (Whenever this deals combat damage to a player, you may have it become an Aura Curse until your next turn. Attach it to that player.)
At the beginning of your end step, Substack Sniper deals 1 damage to you and to each cursed opponent.

At the beginning of each opponent's end step, if no spells controlled by that player resolved this turn, create a 1/1 blue Illusion creature token with “This gets +1/+1 for each other Illusion you control.”

Enchant creature
Enchanted creature gets -3/-0 and can't block.

Trample, haste
Whenever Sugon, Destruction's Fist deals combat damage to a player, return it to its owner's hand unless you have Sugon deal 5 damage to you.

Flying
Whenever you honor a creature, create two 1/1 white Soldier creature tokens.
Whenever you condemn a creature, each opponent loses life equal to its power and you gain life equal to its toughness.

Flying
Suisei the Southern Star gets +1/+1 for each comet counter you have.
Whenever you cast an instant or sorcery spell with mana value greater than the number of comet counters you have, you may pay {R}. If you do, return Suisei from your graveyard to the battlefield, then you get a comet counter.

Menace
At the beginning of your end step, if you lost 4 or more life this turn, you may create Irgh'vall, a legendary 4/4 black Demon creature token with flying.

Enchant creature
Enchanted creature has base power and toughness 3/3.

Whenever a land you control enters, if you haven't had a land become a copy this way this turn, you may have that land enter as a copy of any nonland permanent on the battlefield.

You may have Sun Yun enter as a copy of any creature on the battlefield, except her name is Sun Yun, Master of Man, she's legendary in addition to her other types, and she has “{2}{U}: Exile Sun Yun, then return her to the battlefield under her owner's control.”

If a creature entering the battlefield under your control causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.
{1}{U}, {T}: Exile another target creature. Return it to the battlefield under its owner's control at the beginning of the next end step.

Enchant creature
Enchanted creature gets +3/+3, has trample, and can only attack alone.

Whenever you cast a spell, harmonize. (Trigger up to one harmony of a permanent you control.)
Harmony — Target permanent you control becomes a 2/2 creature with flying in addition to its other types until end of turn.

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.

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.”

Enchant creature
Enchanted creature has haste and first strike.

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.

Enchant land
Enchanted land has “{W}, {T}: You gain 2 life.”

Deception {U}{B} ({U}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Pay 1 life, Choose a creature card name you haven't chosen for Suzume Oshiruko this turn: Return another creature you control with the chosen name to its owner's hand.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Create two 1/1 colorless Construct Actor creature tokens.
II, III — 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.
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Whenever you activate an ability of a card in your graveyard or cast a spell from your graveyard, create a 1/1 blue and black Bird creature token with flying and ward {1}.
Whenever three or more creatures you control deal combat damage to a player, return target creature card with mana value less than or equal to that number of creatures from your graveyard to the battlefield.

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.

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.

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.