Five Best Secrets of Strixhaven in New Standard Meta Flow State If you played through the original Strixhaven era, you likely have some lingering trauma from Expressive Iteration
Karmic Guide is also part of many combos, mostly involving Reveillark, Fiend Hunter, and Altar of Dementia or Goblin Bombardment
Marcy: Since the creature doesn't get haste, I suppose the biggest use for this is to kill something that has a powerful ETB trigger or other impact
However, if you already have some of the cards in the MTG Arena decklist, you will not receive extra copies beyond the maximum specified in the decklist
Getting to discard at will is also a strong proposition
Optimizing the MTG Teenage Mutant Ninja Turtles Commander Deck The release of the Turtle Power