msem-instigator

(Transform this if it's not attached to a creature. Pay {3}{U} as a sorcery to unattach it.)
Enchant creature you control
Gamhaugen Warbeast's rider gets +2/+2 and has flying.

Garden Cherub's power and toughness are each equal to the number of creatures you control.
Garden Cherub can't be blocked by creatures with power 2 or less.

Choose flying, prowess, vigilance, or ward {2}. Create a colorless Equipment artifact token with “Equipped creature has the chosen ability” and equip {2}.

Target permanent phases out. (Then exile this card. You may cast the artifact later from exile.)

Creatures can't attack you or a planeswalker you control unless their controller pays {2} for each of those creatures.
Creatures can't block Ghastly Scraper unless their controller pays {2} for each of those creatures.

Enchant creature
Enchanted creature has “You can't lose the game and your opponents can't win the game.”

Trample
Whenever a creature you control leaves the battlefield, if it had counters on it, put those counters on Golna's Heart.

You gain 7 life. (Then exile this card. You may cast the creature later from exile.)

Flying, vigilance
When you unveil Graced Theurge, draw a card.

Flying

If it isn't an extra turn, take an extra turn after this one. (Cast a copy of this spell once while this creature is on the battlefield.)

Until end of turn, target creature gets +2/+0 and gains “When this creature dies, return it to the battlefield tapped under your control.”

Sacrifice another creature: Grisly Rougarou deals damage equal to the sacrificed creature's power to any target.

{2}, Sacrifice a creature or artifact: Hadak's Guardian deals 2 damage to any target.

Attacking creatures you control get +1/+0.

Enchant player
Creature tokens enchanted player controls get +1/+1.

Indestructible
Whenever Hannaru the Conqueror attacks, put a +1/+1 counter on each creature you control.

Flying
At the beginning of your precombat main phase, you may put any number of land cards from your hand onto the battlefield, then draw a card for each land put onto the battlefield this way.

{W}: Target creature assigns combat damage equal to its toughness rather than its power this turn.

Whenever Haunting Maestro attacks, you may tap or untap up to two target creatures.

Flying, vigilance, deathtouch, lifelink

Enchant creature
When Heartstrings leaves the battlefield, exile enchanted creature.
Whenever enchanted creature attacks or blocks, exile it at end of combat.

(Transform this if it's not attached to a creature. Pay {B} as a sorcery to unattach it.)
Enchant creature you control
Herald of Death's rider gets +1/+1.
Sacrifice a creature: Herald of Death's rider gets +2/+2 until end of turn.

(Transform this if it's not attached to a creature. Pay {4}{G} as a sorcery to unattach it.)
Enchant creature you control
Herdstrider's rider gets +1/+1 for each land you control and has trample.
Whenever Herdstrider's rider attacks, create an X/X green Elephant creature token with trample that's tapped and attacking, where X is that creature's power. Exile that token at the end of combat.

Create X 1/1 blue Boar Dragon creature tokens with flying. (Then exile this card. You may cast the creature later from exile.)