Headaches are a normal symptom for those attempting to make sense of Emperor Palpatine's return in The Rise of Skywalker.
The late-game decision, generally seen as an ass-pull by director JJ Abrams and writer Chris Terrio, and essentially confirmed as such in behind-the-scenes material, was intended to tie all three Skywalker saga trilogies together. However, the manner in which the retcon of the Emperor's death was handled left far more questions than answers, and made fans continue to ponder what the point of everything was.
In The Rise of Skywalker, the explanation for Palpatine's return was provided in the form of a very enthusiastic delivery from Poe Dameron as "somehow". It wasn't until the film's novelization and subsequent ancillary material that fans learned Palpatine's physical body in Episode IX was actually a clone, and the Sith Lord had transferred his essence across the galaxy with great concentration while screaming down the Death Star's reactor shaft to what was presumably his demise.
Complicating matters even further is the retcon of Supreme Leader Snoke's background. Once said to be an ancient being by actor Andy Serkis, Snoke's origins were also retconned in The Rise of Skywalker, which revealed in the opening minutes that Kylo Ren's slain master was actually a clone himself - created by none other than Palpatine.
Many have speculated about Snoke's true purpose in the grand scheme of the re-imagined storyline for the sequel trilogy, and official media has come with mixed explanations that generally leave things vague. A new in-universe book, written from Palpatine's perspective during his time on Exegol, looks to provide a bit more clarity on the matter...
Snoke: A Powerful Puppet for Palpatine
The newly released Star Wars: Secrets of the Sith tells the tale of the Jedi Order's ancient enemies from the perspective of Darth Sidious. One portion of the book, shared by Twitter user JacobsQuest, details more of Palpatine's time in his clone body on Exegol and his intentions for Supreme Leader Snoke.
Palpatine's deformities in The Rise of Skywalker are a result of his decaying clone body, not a Death Star explosion, and one of the early attempts to rectify this by the Sith Eternal was the creation of Snoke:
"As part of their genetic experiments, my followers had attempted to create another being that came to be known as Snoke."
It appears that attempts were made to transfer Palpatine's essence into the Snoke bodies, and failed. However, the fallen Emperor still found a use for the being as a "puppet":
"Although his body proved unworthy of containing my dark essence, Snoke's natural sensitivity to the Force would make him a powerful puppet nonetheless."
Through the Supreme Leader, Sidious was able to create and control the First Order:
"Through my manipulation of Snoke, I began gathering forces, building an army capable of opposing the New Republic that had risen in my absence. Through Snoke, I would make certain that the First Order would be mine to control."
How Much Control Did Palpatine Have?
So... unsurprisingly, there are many questions that this topic raises, and not a lot of answers. The best that can be done for much of this is informed speculation.
As noted previously, The Rise of Skywalker made clear that Palpatine "made Snoke". Beyond this development being a significant deviation from the original background planned for the Supreme Leader, there are considerations that must be made for how much autonomy Snoke truly had.
The visual dictionary for Episode IX and The Star Wars Book suggested that Palpatine inserted Snoke as Supreme Leader of the First Order as a test for Kylo Ren. In defeating his master, Ren was able to prove his worth as the inheritor of the Sith Eternal fleet while Sidious side-stepped the Rule of Two.
Of course, Kylo Ren isn't a Sith, and had no idea he was being manipulated by Palpatine (neither did Rian Johnson at the time). Also worth noting is Palpatine's flip-flopping of whom he wanted to possess between Rey and Ren, with his ultimate plan in The Rise of Skywalker turning the mastermind into something akin to a Scooby Doo villain.
While Senile Sidious' plan in Episode IX makes no sense, there is at least a way for Lucasfilm to justify the retconning of Snoke's background - and it's alluded to in noncommittal fashion in Secrets of the Sith.
One of the many topics of hot discussion in the immediate aftermath of The Rise of Skywalker's release was whether Palpatine had full control over Snoke. The Supreme Leader didn't appear to have a direct hotline to Sidious and serve under him as an apprentice in any way, but the reference to Snoke as "puppet" could mean a few things.
The first and most obvious point of conjecture is that Palpatine acted directly through Snoke. In this sense, Snoke is literally a meat puppet with no free will. In The Last Jedi, the throne room sequence between Snoke, Kylo Ren, and Rey takes direct inspiration from the similar moments in Return of the Jedi - to the point that Snoke says some exact same lines as the Emperor. Between that and the blind luck of John Williams making a reference to the Emperor's theme during Rey's torture, it's possible Palpatine was acting through Snoke the entire time, in retrospect.
Another theory is that Palpatine and his followers planted false memories in Snoke's mind and somehow cut him loose with the goal to create the First Order, corrupt Ben Solo, and achieve dominion over the galaxy. The concept of creating strandcast beings is still an enigma, so planting memories in a being is an even more complicated discussion that probably doesn't have a plausible explanation.
What's most interesting is that Snoke somehow has a natural connection to the Force, but none of the Palpatine clones did. The only successful clone of Palpatine was his "son," which he allowed to live for the sake of procreation by natural means. But why couldn't any of the clones created with his genetic material sustain his power in the Force? And how can an unnaturally created being like Snoke have a natural connection to the mystical energy field? Does it have something to do with Snoke's bizarre relation to Luke Skywalker's severed hand?
Questions, questions, questions. Perhaps some of these things will be answered in next year's novel Shadows of the Sith, but if that scenario proves to be anything like Darth Vader (2020) comic line, things will only grow more complicated.
It's time for some ibuprofen. The Palpatine and Snoke situation is astonishingly convoluted.