Big bad behind the TVA is another version of Loki. - Loki views the TVA as the ultimate power in the universe. There has to be a version of Loki who craves power and likely took it over and created the 3 ruler robots as his cover. - We have seen every version of Loki except a truly evil one. With the show literally being all about Loki, make sense that he would also be the antagonist. -The Kang Therioes are just like like the Mephisto Therories for Wandavision. Make sense to comic fans but that's not the purpose of these MCU shows. The show is about the complexity of Loki seen through the many variants shown in the show.