Exegol (previously called Ixigul) is a dark desert planet located within the Unknown Regions and is a hidden Sith world.
Exegol is a dark, barren, and rocky world with desert flats. The planet's dry conditions combined with the rubbing of dust particles in it's atmosphere created enormous static discharges that appeared as lightning strikes on the surface.
Exegol used to be a fertile planet before the Sith established themselves in there and stripped it of all of its resources, leaving the world barren. The Sith loyalists suspected the existence of a transportative vergence beneath the planet's surface, so they excavated the enormous fissures on its crust trying to find it.
According to legend, Exegol was the hidden world of the Sith because it did not appear any starcharts of the galaxy like other Sith planets, such as Malachor or Moraband. However, it was said that the only way to get to Exegol was through the use of a Sith wayfinder, an artifact created by the Sith to be used as a compass to provide safe passage to Exegol.
After Kylo Ren found one of the wayfinders on Mustafar, he travels to Exegol and meets a revived Darth Sidious that had been hiding for years at the planet. Inside the Dark Lord's lab, Kylo sees many clones of Snoke inside a tank, as Sidious reveals that Snoke was actually an artificial creature that created by Sidious. The Sith Lord offers him the throne of the Sith and the command the Final Order, a massive fleet of Xyston-class Star Destroyers that he had been building since his return, if he kills Rey.
The second wayfinder is found by Rey at the ruins of the second Death Star, but it is destroyed by Kylo right after. Rey then dueled Kylo and saved him from his fatal injuries, before confessing her feelings for him and then leaving aboard his TIE whisper, unknowingly getting the possession of the first wayfinder to Exegol that is inside Kylo's ship. On Ahch-To, she eventually finds it inside his ship and uses it travel to Exegol and also to guide the other members of the Resistance to the planet.
After coming back to the light as a consequence of Rey' and his parents' love, Ben Solo decides to follow Rey to Exegol in order to save her from the Emperor. Ben then finds an old TIE scout in the wreckage of the second Death Star and drives it to Exegol while following the tracking signals Rey is transmitting. The battle of the Resistance against the Sith Eternal forces, results in the Resistance's victory, while Rey manages to defeat Sidious and the Sith with the help of Ben Solo and the Jedi from the past.
- During the beginning of the film, when Kylo Ren arrives at the planet, the several Snoke clones created by the Sith cultists are seen inside a tank. However, when Rey arrives at the planet later, the same tank is shown to be empty. In the novel, this is also noted when Rey walks into the lab and sees "some kind of tank, all empty and abandoned", hinting that their disappearance is not a continuity error of the film, but something done intentionally by the creators of the film and novelization.