The junior novelization for the physical embodiment of the dark side itself. The return of Palpatine in Star Wars 9 remains a major talking point for the sequel trilogy and with good reason. His re-emergence is miraculous, and with no concrete on-screen rationale, it was made all the more unbelievable.
One of the fans many complains about The Rise of Skywalker is that Palpatine's return felt rushed at best, with no substantial time devoted to how he evaded death in clone body, as confirmed in The Rise of Skywalker novelization. There may be more to this story, as the junior novel makes a game-changing claim about his bond with the dark side of the Force.
The Resistance first learns of Palpatine's return via Poe Dameron, who breaks the news to them all at once. There is initial fear among the crowd, but it doesn't take long for speculation to begin on how this is possible. Franchise newcomer Beaumont Kin theorizes it is a result of secret Sith techniques, including dark science and cloning, but there is no way to be sure. Poe goes on to say that "the Emperor did die, but something came back." This suggests that while Sheev Palpatine's physical figure is really gone, his soul lives on as one with the dark side, meaning his appearance in The Rise of Skywalker is as a manifestation of the Force itself.
The Emperor's story arc across his technical daughter Rey on Exegol, he refers to himself as "all the Sith", indicating there is more to him than meets the eye. His power is not his own, channeling those who came before him in a bid for galactic domination. He is the dark side incarnate at this point, void of any semblance of humanity.
At any rate, Palpatine succumbed to his lightning yet again, ridding the galaxy of he and the Sith. For the time being, the Force is in balance with the dark side dissipating alongside the former Emperor. Considering how convoluted his survival was, it was a given there were more powerful entities at play. The Rise of Skywalker is scrutinized to this day for how it handled the iconic villain, but this was the most logical course to take. It only makes sense that he found a way to merge his being with the dark side, becoming its physical manifestation.
