Despite hitting theaters back in December, conversation around Star Wars: The Rise of Skywalker hasn't really slowed down in the months since its release. New information about the galaxy far, far away is constantly being revealed, as well as insider information about the development and shooting of Episode IX. There's a book and comics that accompany J.J. Abrams' blockbuster, one of which recently explained Palpatine's mysterious resurrection.
The novelization of Star Wars: The Rise of Skywalker will hit shelves in a few weeks, although some advance copies have arrived C2E2 in Chicago. The book will greatly expand the story of the blockbuster, which had to contain its narrative in a 143-minute runtime. In Kylo's first meeting with Palpatine, the novel confirmed a major detail about Ian Mcdiarmid's character: he was actually a clone. The body wasn't the same one we saw in the prequel and original trilogies, with his consciousness being brought into a new (decaying) body.
This confirmation from Star Wars: The Rise of Skywalker's novel (via ScreenRant) helps to answer one of the overarching questions still plaguing fans of the beloved space opera. The movie never explained how Palpatine managed to survive his fate at the end of Return of the Jedi, where Darth Vader seemingly killed him before the destruction of the second Death Star. But with the reveal of the villain's status as a clone, we may have a clearer indication of how he eventually reappeared in The Rise of Skywalker.
Sheev Palpatine is the overarching villain of the entire Skywalker Saga. His treachery and manipulation in the prequels led the fall of democracy in the galaxy, as well as the descent of the Jedi Order. All of this was done with methodical planning by the Emperor. And as such, it stands to reason that he might have backup plans if he was somehow assassinated.
Palpatine took control of Clone Army in Revenge of the Sith, revealing that they'd been trained with Order 66 in mind, just waiting to be activated. So it's more than possible that he got his evil hands on all sorts of cloning tech. He would have planned ahead regarding his untimely death, and the Rise of Skywalker novel confirms that he cloned himself in order to return in Episode IX.
An explanation about Palpatine's resurrection was noticeably absent from The Rise of Skywalker, with the filmmakers revealing that they didn't think the specificity of his return was necessary. The story did reveal that Snoke was a clone, but it turns out that the villain and his henchman used the same technology on himself. And as he was in hiding, Palpatine continued to influence the events of the galaxy as the architect of the First Order and Kylo Ren's fall to the Dark Side.