If the allure of power, strategy, and a hint of danger excites you, then the Monarch mechanic is your ticket to ruling the game
Cards you might have discarded with Jace, Vryns Prodigys draw and discards effect, or maybe a removal spell you cast on a bothersome early creature coming back to take out a mid-game threat
Second, being a 5-color legend means you can play the best of the best of your desired creature type with no color identity restrictions.
Each interstellar booster contains Rares and/or Mythics, Traditional Foils, a Borderless basic land, and more
While the commanders used might be more powerful than the tier would suggest, thats usually counteracted by most players not getting the most out of them