When Star Wars: The Rise of Skywalker debuted in theaters it managed to leave a few details at the door and out of the final cut. Though the film was able to introduce a ton of new planets, new characters, and fresh details on its leads, there were some areas where it was lacking, specifically in the "how" some of these things were able to happen. Not only did the new film see the return of Emperor Palpatine but it made sure to reveal that he was not only living on a planet that we'd never heard of, but that he had amassed a following of hundreds and built a new fleet of planet-killing Star Destroyers. The film itself did little to explain this, but answers lie elsewhere.
As reported by MovieWeb, The Rise of Skywalker Visual Dictionary goes into detail about how this was able to happen without anyone in the New Republic noticing. The hooded, Phantasm like figures seen on Exegol are known as "The Sith Eternal," who went about bringing back the Emperor after his on-screen death in Star Wars: Episode VI - Return of the Jedi. This was done using a combination of "technology and the occult," a necessary action given the way he perished at the end of that film.
The Star Destroyers seen in the film are reportedly called the "Xyston-class" versions of the iconic ships, with the Sith Eternal using their influence across the galaxy to smuggle in parts and ships to construct this evil fleet. Also worth noting the book reveals that the crews of these ships (all seen fully staffed in the film!) are made up of the children of the Sith Eternal which includes the red-clad Sith Troopers. Worth repeating, all of this information is found in an ancillary book and not in the 142 minute run time of Star Wars: The Rise of Skywalker.
Apparently none of these moments, such as the resurrection of Palpatine was ever intended to be seen on screen as creature and special make-up effects creative supervisor Neal Scanlan told Yahoo Entertainment that for the most part, the Palpatine fans see in The Rise of Skywalker is what you get. Any additional material was, largely, just variations of the same scenes.
"I don't think there's anything you haven't really seen," Scanlan said. "J.J. would always shoot variations on scenes -- that's the natural moviemaking process. But to my knowledge there's no alternative version [of Palpatine's story]. We change camera angles, we change lighting, maybe there's a dialogue variation. It's just naturally what we do."
Star Wars: The Rise of Skywalker is in theaters now.