Force spirits, also known as Force ghosts, were beings who gained immortality through the preservation of their consciousness after death. When lifeforms died, they became one with the Force.
Those who died and passed into this netherworld of the Force generally could not affect the material world. However, some individuals can train during their lives to become Force Ghosts, retaining the ability to influence the galaxy after death.
This implies that Force ghosts are not actually immortal, in Legends at least. While Obi-Wan's Force ghost faded away after 9 years, Luke's Force ghost appears to Cade Skywalker much longer after his death.
Summary. The ending of The Rise of Skywalker sees Leia as a Force ghost, but it's never explained how she was trained to do this after her death. Leia's ability to become a Force ghost isn't far-fetched, as she had three Jedi Masters who could have taught her - Luke, Obi-Wan, and Yoda.
Qui-Gon Jinn was the first character in a film to show Star Wars audiences that not all Jedi became Force ghosts upon dying (by virtue of his body not disappearing at death), but he was established in Attack of the Clones as a voice addressing Anakin Skywalker, and also in Revenge of the Sith as the first (by ...
Force Ghosts: Everything You've Ever Wanted to Know (Star Wars Canon)
Why was Ben not a Force ghost?
Originally Answered: Why doesn't Ben Solo appear as Force Ghost? Because he's now literally a part of Rey. Earlier in the movie, Rey healed that snake thing and said she transferred part of her life force to it. That was foreshadowing that when Rey died it look all of Ben's life force to grind her back.
Why didn't Mace Windu showup as a force ghost? Qui Gon died before he could finish his training so he can only appear as a voice and not a physical form. Mace Windu never studied or trained in that aspect of the force.
Not only does it appear that only Jedi can see Force ghosts, but there's a heavy implication that communing with them is a skill in itself. This would explain Leia's apparent inability to see the three ghosts in Return of the Jedi's finale, despite the fact she was actually Force sensitive.
The closest that Star Wars canon has come to naming who trained Yoda was revealing that Jedi Master Qui-Gon Ginn was the one who taught Yoda to become a Force Ghost and attain immortality.
In material that is now considered Legends, Qui-Gon is even described as a Gray Jedi. Additionally, the term has also been applied to Force-sensitives who aren't affiliated with the Light or Dark side of the Force. Quite literally, these Gray Jedi don't see things in black and white, or light versus dark.
We are led to assume this as in TCW Qui-gon admits his training was incomplete. He could only appear on Mortis, anywhere else he could only be a disembodied voice. Wait, if he hasn't completed the training, how did Obi-Wan?
For those who use the corrupted dark side of the Force like Sith Lords, returning as a spirit is dangerous, violent, and chaotic, often restricted to a specific place or object. Fascinatingly, beings who aren't Force-sensitive have an afterlife in the Force, but they cannot return as ghosts.
George Lucas similarly could have added Qui-Gon Jinn to the Force ghost mix if he deemed him an appropriate inclusion. However, Qui-Gon Jinn played no part in the original trilogy whatsoever, so having him appear would have been entirely out of place for the story.
Summary. Rey received guidance from the voices of past Jedi, including Obi-Wan Kenobi and Anakin Skywalker, who encourage her to rise and defeat the embodiment of evil. Ahsoka Tano's voice reached Rey through the Force, suggesting she must have rejoined the rankes of the Jedi before her death.
Somehow, Obi-Wan or Yoda taught him how to become a Force ghost in time for Luke to see him in Return of the Jedi. Another theory stated that Kylo couldn't become his own Force ghost because he and Rey were part of a Force Dyad, meaning that his consciousness was absorbed into Rey when he died.
Due to Klaus's ability to manifest the dead into the living world, it's entirely possible that Ben's ghost ages because of his strong connection to Klaus. While Klaus is able to send other ghosts away, Ben is always there, making Klaus an anchor of sorts to the real world.
Though initially trained as a Jedi by his uncle Luke Skywalker, Ben was seduced to the dark side of the Force by Supreme Leader Snoke, and aspires to be as powerful as his grandfather, the Sith Lord Darth Vader / Anakin Skywalker.
The crossguard blades allow Ren's saber to operate safely – his weapon is constructed around a dangerously flawed kyber crystal, which would be overloaded if not for the lateral plasma vents that create the quillons.
...was redeemed at the end like Vader was. We will see a force ghost of Maul who will be trained by Qui-Gon to be able to live forever in the Force. He accepted his defeat and the Dark Side died inside of him in his last moments as Kenobi held him.
He was Palpatine's genetic creation, one who hadn't genuinely mastered the ways of the Sith and, thus, he was not an actual Sith Lord. Nevertheless, Kylo killing the one he believed was his master was undeniably in keeping with Sith tradition.
