When Disney purchased Star Wars, many fans were disheartened to find out that the Expanded Universe novels were no longer going to be considered canon. Rather, they would be deemed Legends, and new publishing initiatives would begin to create a different novel series that ties into the beloved franchise.

However, as the Star Wars canon has expanded, certain pieces of the Legends universe have made their triumphant return to the canon. Here are ten pieces of Legends that have come back and played a major role in recent additions to the Star Wars saga.

10 Force Projection Proved to Be a Valuable Skill

The concept of Force projection is one of the most interesting abilities in the Star Wars universe. Also known as Similfuturus in High Galactic, the tactic allowed the user to create an identical version of themselves using the Force and send them out to various locations in the galaxy. While using the projection, the creator experienced the same sensations as the projection, just without any of the danger that came with going into potentially treacherous locations. When used by someone particularly skilled, projections could be created of anything, not just the user (though this, known as a Force phantom, was often considered to be a dark side ability and therefore wasn't used by the Jedi).

In canon, Luke Skywalker was the first person to execute Force projection - something he also did in the Legends continuum. The general technique remained the same, with the creator making a version of themselves that, other than being noncorporeal, could not be distinguished from their true self. Using this, Luke sent the projection to the Battle of Crait, where he faced off with Kylo Ren to give the Resistance the chance to escape the base they were trapped in unscathed. The effort exhausted him, however, and he passed away as soon as the vision disappeared.

9 Mandalore Is One of the Galaxy's Most Important Locations

Mandalore is one of the most important planets in the Star Wars galaxy. It first appeared in a Legends comic book back in 1977, right after the original release of A New Hope. Princess Leia tracks a bounty hunter named Dengar to the planet, where he plans to capture Fenn Shysa, who was training a new cohort of Mandalorian Protectors. There, she found herself involved in Mandalore's fight for freedom against the Empire. The seeds of Mandalore as fans know it in more recent entries to the saga are planted in this comic, though it still underwent a lot of changes when it was brought to the wider Star Wars universe.

Throughout the Clone Wars, Mandalore proved to be a significant theater of combat. In the years before the war, the planet dealt with a lot of infighting, which left the majority of the territory inhospitable. Satine Kryze attempted to rule the planet through pacifism and gentleness, but she was overthrown by Darth Maul and his Shadow Collective, which led to even greater political instability in Mandalore. Ultimately, this culminated in the Siege of Mandalore, depicted in the final arc of The Clone Wars. It resulted in the destruction of the planet as a whole at the hands of the Empire. It's one of the most tragic stories in the galaxy.

8 Fortress Vader Was the Villain's Home Base

Though Fortress Vader didn't exist in its original incarnation in Legends, there was something very similar to it: Bast Castle, a massive black structure where Vader spent most of his time when he wasn't doing assignments for the Emperor. An elite group of Stormtroopers defended it from anyone who would dare to infringe upon Vader's home. While there, he worked on studying the skills he would need to heal his grievous injuries and honed his mechanical skills by tinkering with his TIE fighter and repairing droids that he injured while sparring with them.

Fortress Vader draws inspiration from Bast Castle. First and foremost, the two look nearly identical. Fortress Vader also gave its owner a place to recover from his injuries, though he had a bacta tank rather than trying to heal himself using newfound Force abilities or anything like that. It had a reputation throughout the galaxy as being the sort of place Jedi who entered didn't leave, as stated by Kanan Jarrus in Star Wars Rebels.

7 Crossguard Lightsabers Are a Cool New Weapon

Crossguard lightsabers are some of the coolest weapons in the Star Wars canon. They first appeared in the Jango Fett comics back in 2002 - years before they made the jump to canon. There were numerous versions of the crossguard lightsaber, each with slight variations from their predecessors. For example, one of them had a physical crossguard on the hilt of the saber. Others, much like Kylo Ren's in the eventual canon incarnation of the weapon, had actual lightsaber blades that acted as the crosspieces. Some others had dual blades to begin with before the vents were added, making them even more dangerous.

Since their return to canon, more users have become prevalent, though they're still one of the rarest types of lightsaber. Stellan Gios wields one throughout his appearances in the High Republic novels, and it was popular enough that Disney released a replica of it that fans could purchase. Cal Kestis had the potential to use a crossguard saber in Jedi: Survivor, once again bringing the unique weapon type to greater attention. And, of course, there was Kylo Ren, whose crackling crossguard saber became one of his greatest trademarks.

6 Force Healing Has a Complicated Past

Force Healing, in its original incarnation, was fairly common. Any Jedi could learn to wield the power. There were even people simply designated to be healers for the Jedi who dedicated all their attention to learning how to heal their companions with the Force (something that has, unfortunately, not yet become prominent again). As Jedi got better at using it, they could take care of more serious injuries. Those with immense talent could even mend organs that had ceased functioning or something just as grave as that.

When it was brought to canon, however, it became a much more taxing ritual, and therefore very few Force users dared to take it on. Though it was an inherently good tactic, the openness it required often led its users to deal heavily with the dark side, as they were taking on so much of the target's pain. The Sith also took particular interest in the idea of Force healing, though in part because it meant they could use someone else's life energy to restore their vitality. Anakin Skywalker used a variation of it on Mortis to heal Ahsoka, though its first true appearances were near-simultaneously in The Mandalorian and The Rise of Skywalker.

5 Malachor Underwent a Few Changes on the Journey to Canon

In Legends, Malachor has a remarkably complex role to play on the galactic political scale. The Sith Empire colonized it, though they eventually abandoned it before the beginning of the Mandalorian War. During that conflict, it was the site of the final battle (and the most destructive). Jedi General Revan slaughtered the leader of the Mandalorian forces, and in the aftermath of the battle, the surface of the planet was scoured to the point of inhospitality. It later became the site of a conversion site used by the Sith when they captured Jedi Knights and worked to lure them to the dark side to strengthen their causes. Darth Traya turns it into her home base, though she is eventually exiled from Malachor after her apprentices overthrow her.

In canon, Malachor also plays a major role in the Sith's history. It's the home to a Sith temple that houses a massive weapon that's only been set off once in the galaxy's past: during a deadly battle known as the Great Scourge of Malachor that led to destruction on a scale that has rarely been seen again. It was the site of a confrontation between Kanan Jarrus, Ahsoka Tano, Ezra Bridger, and Darth Maul, who sought a Sith Holocron located inside the temple. Though Maul proved to have ulterior motives, they brought down three Inquisitors before the truth came out. As if things couldn't get worse, Darth Vader showed up to finish the job himself - and had to face his former apprentice. For a while, it looked like Ahsoka died on Malachor, though she ultimately survived by entering the World Between Worlds.

4 Sabacc Was a Major Part of Han Solo's Life

Sabacc, a beloved card game, is one of the small details that make the Star Wars galaxy feel that much more real compared to other fictional universes. It's a pastime that many popular characters, such as Han Solo and Lando Calrissian, took part in (at times so often that it proved to be detrimental). It played a major role in one of the opening scenes of the novel in which it originated, which followed Lando as he searched for ancient treasure in the Rafa System. Over a game of sabacc, he meets Osuno Whett, who tells him about the treasure in the first place. This kickstarts the entire plot of the novel.

Though Sabacc's first canon appearance comes in a novel about Kanan and Hera, its most prominent lovers are Han Solo and Lando Calrissian. Numerous different sabacc games had massive consequences for the two men. The most notable match, of course, came when Han Solo won the Millennium Falcon off Lando on Numidian Prime, something that shaped the nature of their relationship throughout the rest of their appearances in the franchise. Another time (also with Lando), Zeb Orrelios lost his team's beloved droid Chopper on an unlucky hand and had to struggle to get him back.

3 Cortosis Recently Became More Prominent

In Legends, cortosis made up the majority of Shadowtrooper armor, since it was resistant to lightsabers. It was nearly impossible to mine, as the raw energy surrounding it made it lethal to anyone who came into contact with it before it had been refined. However, finding it remained an incredibly worthwhile endeavor for the Empire, who used it in any scenario they could think of. Even the walls of the Imperial Palace had it running through them. Various weapons were made of the material, and against those, Jedi could hardly stand their ground.

Though this isn't the first canon appearance, many fans thought they spotted more homages to cortosis in the fifth episode of The Acolyte. Lightsabers shorted out when they hit the Stranger's helmet, making many wonder if this was the moment they had waited for, and if this aspect of Legends would finally get its dues in front of a wider audience. The sixth episode only confirmed everyone's suspicions. When Osha touched Qimir's helmet, he stated that it was made of cortosis - and that it was a sensory deprivation helmet, like the Order used to train its younglings.

2 Nightsisters Have Had a Lasting Influence

Though the Nightsisters of Dathomir were introduced in The Courtship of Princess Leia, they underwent a bit of evolution to become the group seen throughout canon today. They weren't the only group of witches on Dathomir; rather, they were the most powerful and often used their greater abilities to exert influence over the other clans. They aspired toward galactic domination - something that, though Mother Talzin may have liked to have, she never really put forth the effort to achieve. Though they were wiped out in Legends, much like they were in canon, there were enough survivors that they were able to reclaim their position as the most powerful beings on Dathomir. In the aftermath of this, they aligned themselves with the Sith.

In canon, they were a bit less explicitly evil. Rather, they didn't separate things into light and dark as the Jedi did - allowing them to tap into the dark side of the Force without actually falling into darkness as others might. They tapped into the power thrumming beneath Dathomir's surface to utilize their magick, which could take a variety of forms. The civilization ultimately met a tragic end when, after a perceived betrayal, Count Dooku sent General Grievous to eliminate the women. Only a few survived, including Nightsister Merrin and Morgan Elsbeth.

1 Grand Admiral Thrawn Is the Most Prominent Figure to Carry Over from Legends

Grand Admiral Thrawn was one of the first characters created for the Legends universe. In the books, he was the only non-human Grand Admiral, which speaks only to highlight his immense power. In the aftermath of the Battle of Endor, during which he hid in the Unknown Reasons to prevent his death in the same conflict as Darth Vader and Palpatine, he took control of the remaining Imperial forces to destroy the New Republic. He posed the greatest threat to the fledgling government, as his military prowess made him nearly impossible to stand against. However, he eventually met an untimely end at the hands of Noghri assassin Rukh during the Battle of Bilbringi.

The version of Thrawn presented in Star Wars Rebels is, for the most part, very similar to the one in the original books. He maintains his desire to ensure the success of the Chiss Ascendancy above all else, and his military tactical skills remain unrivaled. He works to understand every aspect of his enemies before he launches an attack, believing that to defeat someone fully, you must comprehend who they are. He'll likely continue to be a threat in future installments to the series since he came to live action in Ahsoka and appears to have massive plans for galactic domination in potential upcoming seasons.