If built and piloted well, mill can be a potent strategy in Commander
Will they make and unmake it like Penelope, or does their story unfold differently
First of all, discarding cards is not always necessarily bad, depending on what you discard, of course
Cynthia's Ambition and Roseanne's Backup both come in Rainbow variants, too, which have been reported as having pull rates of nearly 1/1000
All it takes is a Grand Prix top 8 with either of those cards during Modern season
If you read between the lines, for 4 mana on the first cast, you get to choose from 16 cards in a full-sized Commander table that then can be cast to assemble your remaining combo or just find the combo pieces you need to kill them on the next turn with, of course, Demonic Consultation + Thassa's Oracle