Immortality

In 19 BBY, having completed his plan to turn Anakin Skywalker to the dark side of the Force, Darth Sidious claimed his late master Darth Plagueis to have gained the ability to cheat death and to preserve the lives of the ones he loved by influencing midi-chlorians. Sidious also stated that his master was slain in his sleep after the knowledge was passed on to his apprentice. Finally, however, he retracted that statement and admitted he had not attained the deceased Plagueis' knowledge, insisting that it could be discovered if Skywalker and he worked together.

While Sidious shared the Tragedy of Darth Plagueis with Skywalker, he asserted that the dark side of the Force could provide one with abilities deemed by some as contrary with nature. He maintained that stance in 35 ABY shortly after the broadcast revealing his forthcoming revenge to the galaxy.

In addition to Plagueis' skills, which allegedly enabled him to save people from death, there existed several methods which allowed one Force-sensitive to use Force drain or healing to resuscitate another through resurrection. The individuals wielding those skills included Anakin Skywalker—who resurrect Ahsoka Tano by extracting the Daughter's energy as she died—and Ben Solo, who resurrected Rey, his co-participant in the dyad of the Force, at the cost of his own life.

Every living being became one with the Force during the process of dying. Once transformed from the living into the cosmic Force, the majority of them lost their consciousnesses and sentience, with only a handful gaining the ability to preserve both their self-awareness and physical appearance, occasionally manifested in the form of bluish Force spirits. The Jedi did not recognize that possibility up to the final days of the Republic.

The notable individuals to master the technique included the Force Priestesses and the Shaman of the Whills. The latter relayed the knowledge to Qui-Gon Jinn, yet since Jinn's training was incomplete as of his death in 32 BBY, his body did not vanish. The Jedi was initially capable of communicating as a voice only. Even so, he completed his training post mortem by 9 BBY, at which point he showed himself to Obi-Wan Kenobi during the latter's seclusion on Tatooine. In addition, during the Clone Wars Jinn's spirit appeared in a vision to Anakin Skywalker. Some, including Skywalker, came to believe that experience to be an actual spiritual manifestation of the late Jedi.

Foreseeing Yoda's relevant role in training the one who would preserve the balance of the Force, Jinn communicated with the Jedi Master during the final days of the Clone Wars and instructed him on his way to the Wellspring of Life, where he was supposed to undergo a preliminary training supervised by the Force Priestesses. With Yoda's suitability proven, Jinn promised to conduct the training onward. Yoda himself passed on the knowledge to Obi-Wan Kenobi and taught him to communicate with Jinn. Both Yoda and Kenobi were soon among a handful of the last Jedi survivors and both preserved their consciousness in 0 ABY and 4 ABY, respectively. In 4 ABY, Anakin Skywalker, the Chosen One, who had once fallen to the dark side and declared himself as Darth Vader, was redeemed and his spirit soon joined those of Yoda and Kenobi before appearing to Luke on Endor.

Luke Skywalker became another Jedi to reach immortality, his corpse vanishing on the planet of Ahch-To in 34 ABY. The following year, Skywalker was able to appear to Rey, a manifestation that coincided with Leia Skywalker Organa Solo's death, whose dead body did not disappear until her son's corpse did alongside hers.

The individuals whose bodies vanished also included the Father and Ben Solo. The latter could communicate with living beings, and his co-participant in the dyad of the Force, Rey, could hear his voice while eyewitnessing his body's disappearance.

Mother Talzin was blessed by an unnaturally long life due to magick. Via certain aspects of the dark side combined with their mystical magick, the Nightsisters were known to manifest as greenish phantoms in their post-mortem existence. In 19 BBY, while Asajj Ventress' body was being buried on Dathomir, they could be heard whispering and murmuring something to one another. During the Imperial Era, Maul allied with their spirits via his promise to provide them with physical bodies to serve as new vessels. In return, they consented to merge his mind with that of Ezra Bridger, and when the ritual was complete, the ghosts possessed Kanan Jarrus and Sabine Wren, even though Ezra Bridger eventually liberated them by fracturing the altar, as they could only appear within a short distance from it.

In addition, the Nightsisters could arrange a special ritual to resuscitate the dead in the form of zombies.

Through ancient dark side masks, both Darth Momin and Exim Panshard where able to preserve their consciences far beyond their natural death. Presence was a Sith known to retain a facet of her presence in the holocron once belonging to her. In the Imperial Era, she spoke to Ezra Bridger this way multiple times.

After Kanan Jarrus died, his will was conveyed onward by a Loth-wolf identifying with the name Dume. Inside the World Between Worlds, Ahsoka Tano stated that contacting dead beings through animals was not impossible.

Penn Pershing, a scientist of an unidentified planet who would eventually work for Moff Gideon's Imperial remnant, was interested in the prospects of cloning to enable one's loved ones to cheat death, an interesting concept that was sparked to him by his mother's death, feeling that had he been able to clone organs, he could have prevented her passing from a heart failure.

In the fear of his incoming death, Darth Sidious ordered that an exact clone of his body be engineered as a new vessel for his spirit. Thus, once thrown down a shaft onboard of the Death Star II, he transmitted his awareness to the clone, leaving the original body falling down to certain destruction.

Aware of the new body's imperfection, Sidious sought another vessel to host his spirit. When a clone of him parented a child, he enjoined that the girl be brought to him so he could pass on to her body. However, the hunter Ochi, tasked with that mission, failed to locate her and died without attaining her location. Sidious renewed his plan in 35 ABY, futilely encouraging Rey to kill him so that his spirit could possess her body. Regardless, the clone body was ultimately restored to a powerful version through the extracting of the power shared Rey and Ben Solo as a dyad in the Force.

Ultimately, the Emperor's vision of a galaxy eternally ruled by the Sith ended when his clone body was destroyed by his own power. Sidious was vanquished in both body and soul, and his dream of immortality died with him.

Between the years 34 and 35 ABY, Rey underwent training by Leia Organa, which provided her with a method to muster the past Jedi's spirits to assist her in bringing an end to the First Order. Shortly before the eventual clash between her and her grandfather, she invoked those spirits to succor her in exploiting her inner power to overcome the clone. Shortly before his death, Palpatine claimed to be all the Sith.

The artifact known as the Ring of Immortality, one of the two Rings of Vaale created by the Architects of Vaale, was said to provide its wearer with immortality but at the cost of driving them to madness, yet its negative effects could be removed supposedly if the wearer also possessed the Ring of Fortune.

According to legend, Exegol was once visited separately by Darth Sanguis and Darth Noctyss in their quests for immortality. However, Sanguis became immortal through a ritual which transformed him into a horrendous creature. When Noctyss met him and became aware of Sanguis' achievement, Sanguis tricked her by not revealing his true identity so she would kill him in the very same ritual. Noctyss did so and Sanguis was freed from his miserable existence, leaving a transformed Noctyss alone at Exegol.

Doctor Cylo, one of the Galactic Empire's best scientists, resolved to use illegal alien parts smuggled to his secret base during his research to create new life forms with technological augmentations, creating a personality map that, completed with memory banks and plug-in calculation systems, allowed himself to become an immortal system with several upgraded bodies at his disposal to use whenever his previous one died. Cylo survived several deaths through this way until Darth Vader finally killed him in a star of the Kuat system. The Corellian bounty hunter Rothgar Deng subjected himself to cybernetic replacements and turned to black market surgical clinics to replace his damaged body parts in order to live and work forever.

The starbird of legend was said to be immortal, able to renew itself in the heart of a nova when it was believed to be dead.

The sarlacc of the Great Pit of Carkoon allegedly digested its prey for millenia, thus keeping its victims alive during all that time for it to slowly consume. Protocol droid C-3PO, when told by the Hutt crime lord Jabba Desilijic Tiure about the planned execution of his rebel friends, informed them that, according to Jabba, anyone on the sarlacc's belly would find a new definition of pain and suffering as they got digested over a thousand years.

• Sabine My Rebel Sketchbook
• Star Wars: The Rise of Skywalker: The Visual Dictionary
• The Star Wars Book
• Star Wars: The Secrets of the Sith
• Star Wars: Dawn of Rebellion: The Visual Guide