A core tenet of the Rule of Two is a Sith Grasp passing their energy and information onto their apprentice as soon as the latter kills them. It ensures that there is all the time a succesful grasp current with an rising scholar beneath them, able to take their place and stick with it Sith rule. Nonetheless, Emperor Palpatine, aka Darth Sidious (Ian McDiarmid), does not appear to carry a lot inventory within the Rule of Two because it’s written. In each “Star Wars” canon and “Star Wars” Legends, it is evident that he seeks energy for himself and himself alone, going so far as evading demise.
In canon, Sidious takes on a number of apprentices, however he is not desperate to let his energy cross to them. Along with his remaining learner, Darth Vader (Hayden Christensen, who made a hilarious reveal relating to the Sith’s underwear) at his facet, Sidious takes a vested curiosity in cloning. As seen in “Star Wars: Episode IX – The Rise of Skywalker,” he makes use of the know-how to remain alive, transferring his consciousness to a clone physique to regain his misplaced energy following his obvious demise many years earlier. He does one thing related within the Legends story “Star Wars: Darkish Empire,” getting back from the grave in a clone physique in hopes of ruling the galaxy once more. In Legends, this is called the Rule of One — or Palpatine’s Doctrine.
Seeing as Darth Sidious is defeated by Rey Skywalker (Daisy Ridley) on Exegol, many years after being defeated by Vader and his son, Luke Skywalker (Mark Hamill), it is plain to see that the Rule of One is simply as ineffective — if no more so — than the Rule of Two.