The Star Wars universe is vast and continues to expand. Many new "Star Wars" shows are either in production or will begin filming soon, including "The Book of Boba Fett," "Andor," "Kenobi," "The Acolyte," "Ashoka," and future seasons of "The Mandalorian." There are also new films in development, the first of which, "Rogue Squadron" from director Patty Jenkins, will debut in 2023.

But Star Wars has always had life beyond the movies and spinoff series. Other media, including books, comics, and games have been part of the franchise since the beginning, with the first spinoff novel, "Splinter of the Mind's Eye," and a Marvel comics series released a year after the original 1977 film. The so-called Expanded Universe reached even greater heights in 1991, when Timothy Zahn's novel "Heir to the Empire" and the comic series "Dark Empire" proved that printed Star Wars stories could be just as exciting as the films themselves.

The Expanded Universe generated hundreds of new characters, locations, and events in the Star Wars universe. Much of the older Expanded Universe is now deemed non-canon, as Disney chose to relaunch the timeline after purchasing Lucasfilm in 2012. Still, since then, some Expanded Universe characters have been brought into the movies and TV shows — Grand Admiral Thrawn, for example, appeared in "Star Wars Rebels." But not every character gets that chance. These great Star Wars characters have yet to appear on screen — with any luck, it's just a matter of time.

Doctor Aphra

One of the most exciting ongoing storylines in the "Star Wars" universe at the moment is the "Doctor Aphra" comic book series, which follows the adventures of a young archeologist during the events of the original trilogy. Aphra was first recruited by Darth Vader to act as his personal spy, and they bonded through their shared technical expertise as Aphra embarked on missions for the Sith lord by integrating herself among the ranks of smugglers and bounty hunters. The partnership was short-lived, however, as Vader betrayed his former agent and forced her to go on the run. Aphra would reluctantly work alongside the Rebel Alliance as she searched the galaxy for mysterious artifacts.

Employed by various criminal organizations, Aphra has a flexible moral code. During her adventures, she's crossed paths with characters like Hera Syndulla and Luke Skywalker, and despite an on-again off-again romance with Rebel agent Magna Tolvan, she has yet to pledge allegiance to just one faction. Aphra is involved in the ongoing "War of the Bounty Hunters" storyline, in which the criminal underworld competes to steal Han Solo's carbon-frozen body from Boba Fett.

Alpha-17

Although the animated series "The Clone Wars" explored the conflict first mentioned by Obi-Wan Kenobi in "A New Hope," it was hardly the first story set within the era. Between the releases of "Attack of the Clones" and "Revenge of the Sith," many Expanded Universe projects explored the war, including the long-running comic book series "Republic." Among the Republic heroes introduced in the series was the ARC Trooper Alpha-17, who served alongside Anakin Skywalker in the 501st Battalion.

Compared to his by-the-book brothers in arms, Alpha-17 had an independent streak that earned him Anakin's respect. The cloning scientists on Kamino enhanced the specialized ARC Troopers, giving them advanced fighting techniques and strategic impulses reminiscent of Jango Fett. As a result, clones like Alpha-17 were assigned independent combat duties. Alpha-17 aided Anakin and Obi-Wan in their pursuits of fearsome enemies, such as the bounty hunter Durge and the Sith apprentice Asajj Ventress. Alpha-17 was critically wounded during a battle with General Grievous, which left him out of commission during the events of Order 66.

As revealed in "The Art of Star Wars: The Clone Wars," George Lucas and Dave Filoni considered making Alpha-17 the primary clone character in "The Clone Wars," but ultimately decided to create a new character, Captain Rex. Many of Rex's personality traits, including his independence and friendship with Anakin, were adopted from Alpha-17.

Darth Zannah

Darth Bane was one of the most important figures in the Star Wars Expanded Universe, as he was the Sith Lord that established the "Rule of Two." Previously, Sith numbered in the thousands, but their thirst for power led to instability as rival lords annihilated each other. Bane massacred the Sith, took on an apprentice, Darth Zannah, and hid their existence from the Jedi, convincing them that the threat of the dark side had been defeated. While Darth Bane appeared on screen as a spirit in "The Clone Wars" episode "Sacrifice," his equally fearsome apprentice hasn't appeared in any new materials.

Zannah was recruited by the Jedi Order when she was a child, but after witnessing her mentor Laa's death at the hands of a Jedi Knight, she grew a thirst for blood. After slaying the Jedi lnight with her untapped Force-powered rage, Zannah caught the attention of Bane, who decided the child had the potential to be his ally. Bane trained Zannah as his apprentice and gave her the "Darth" title, but after he saw that her powers rivaled his own, he plotted her demise. Bane was unable to escape his apprentice's blade, and Darth Zannah became the new Sith master alongside her own apprentice, Darth Cognus.

Jax Pavan

Although Order 66 wiped out most of the Jedi Order, a few Jedi survived and lived in hiding as the Galactic Empire took control of the galaxy. Jax Pavan's life began with tragedy; his father Lorn was a low-level worker within the Jedi Temple who discovered that his child was Force-sensitive, but Lorn was killed by Darth Maul while protecting his infant child. Fulfilling his father's dying wish and becoming a Jedi, Jax Pavan became a hero in the Clone Wars and a close friend of Anakin Skywalker. He was granted the rank of Jedi Knight shortly before the Jedi massacre, and managed to survive the betrayal of the clone troopers by hiding in the Coruscant underworld.

Jax's adventures were chronicled in the "Coruscant Nights" novel series, in which he became a private detective and assembled a company of allies that included his father's droid, I-Five. Despite distancing himself from the ways of the Jedi, Pavan's new venture caught the attention of Darth Vader, who became obsessed with finding the Jedi fugitive. During their confrontation, Jax discovered the dark lord of the Sith was none other than his former friend, Anakin.

Darth Revan

"The Old Republic" encompasses an ancient era of the "Star Wars" timeline set thousands of years before the films, and produced many exciting new characters and storylines. The Sith were not yet bound by the Rule of Two that limited their numbers to just one master and apprentice; their empire had thousands of members. One of the most fearsome Sith lords was Darth Revan, one of the central characters of the "Knights of the Old Republic" video game. Revan was raised in the ranks of the Jedi and became a hero through his conquests during the Mandalorian War, ending the Jedi's conflict with the warrior clan by defeating Mandalore the Ultimate.

Revan's heroism was short-lived, however, as he was seduced by the dark side and formed a new Sith Empire alongside his apprentice Darth Malak. Revan created a new fleet using an ancient Sith space station called the Star Forge, but Malak ultimately betrayed him and left his master to be captured by the Jedi. Revan's mind was wiped by his former archnemesis, the Jedi Knight Bastila Shan, and he once again became an agent of the light side.

Revan's distinctive mask and interesting backstory made him a favorite among fans, and he almost made the transition to screen. Revan was featured in a deleted scene from "The Clone Wars" episode "Ghosts of Mortis" as part of a Force vision, but has not appeared since.

Prince Xizor

The "Shadows of the Empire" project from 1996 was one of the most ambitious storylines in the Star Wars Expanded Universe. A connected narrative told through a novel, a comic book series, a video game, role-playing games, merchandise, and even an official soundtrack chronicled the events between "The Empire Strikes Back" and "Return of the Jedi." As Luke, Leia, Chewbacca, and Lando searched for Han and his captor Boba Fett, they faced threats from both the criminal underworld and Darth Vader. Prince Xizor, head of the Black Sun crime syndicate, agreed to aid Emperor Palpatine in the search for Skywalker in order to earn a place at the Emperor's side.

Black Sun was a feared organization that ran networks of spies and assassins throughout the galaxy, and its leader was both ruthless and affluent. Xizor infiltrated Coruscant's high society with his charismatic nature, which masked his brutal tactics. Xizor held an intense hatred for both generations of Skywalkers; his homeworld, Falleen, was massacred when Darth Vader unleashed a biological weapon. Upon discovering that Luke was Vader's son, Xizor vowed to track down Skywalker. Although he plotted to replace Vader as the Emperor's chief lieutenant, the shrewd Sith lord killed Xizor by destroying his flagship, Falleen's Fist.

Xizor has yet to appear in any new Star Wars projects, but the Black Sun organization appeared in "The Clone Wars" and "Rebels" as part of Darth Maul's criminal empire.

Darth Malgus

The ancient Sith lord Darth Malgus was first introduced in the cinematic teaser trailers for the MMORPG "The Old Republic," which followed a massive schism between the Galactic Republic and the Sith Order set over three thousand years before the events of the films. The war began with the destruction of the Jedi Temple on Coruscant, a devastating attack led by the masked Sith warrior Darth Malgus, who slew members of the Jedi Council and forced the Republic into ceding territory to the Sith.

Malgus' story continued in spinoff novels and further cinematic trailers. Brutal even by Sith standards, Malgus was uninterested in political maneuvering, preferring to lead combat missions himself, and often employing alien and Mandalorian warriors. Malgus helped retake the Sith homeworld of Korriban (renamed Morriban in the new canon), and slew his own master, Darth Vindican, in a bid for more power. Malgus's body was deformed at the hands of the Jedi Knight Satele Shan, but the pain only fueled his rage as he annihilated both Jedi and Sith alike

Cade Skywalker

The Skywalker bloodline lived on well past Luke and Leia's generation in the "Legacy" comic book series, which imagined events set over 130 years after the end of "Return of the Jedi." Once again, the Empire has risen in opposition to the Galactic Alliance (the governmental body that replaced the New Republic), and the Jedi Order was caught in the crossfire. The "One Sith" order under Darth Krayt leads an assault on the new Jedi Temple, and among the few survivors was Cade Skywalker, Luke's last surviving descendant.

Cade was raised knowing his family history, but in order to protect himself during the new reign of the Sith, masked his identity and took up a life as a bounty hunter. Allied with fellow criminals Deliah Blue and Jariah Syn, Cade is reluctantly called back to his destiny when he becomes one of Krayt's targets. Although the Sith assassin Darth Talon attempts to seduce him to the dark side, Cade ultimately chooses a heroic path.

Galen Marek

"The Force Unleashed" was one of the most popular "Star Wars" video games of all time, letting players test out groundbreaking Force abilities through the game's central character Galen Marek. The orphaned son of a Jedi survivor of Order 66, Galen was captured and raised by Darth Vader, who trained him as a secret apprentice under the codename Starkiller.

Vader tasked Starkiller with hunting down surviving Jedi, including prequel trilogy character Shaak Ti and the newly introduced Rahm Kota, a Jedi warrior who had survived Order 66 because he chose to train his own men instead of relying on clones. Although successful in wiping out many Jedi, Starkiller was betrayed by Vader after Emperor Palpatine suspected the two would attempt to overthrow him. Left for dead by his former master, Starkiller started down a path of redemption and trained under Kota to become a force for good.

Retiring the name Starkiller, Galen Marek helped the early Rebel Alliance secure the plans for the Death Star and shielded Bail Organa from a surprising Imperial assault. Ultimately, Marek paid the ultimate price and sacrificed his life during a battle against Vader and the Emperor on the bridge of the newly constructed Death Star. Vader still had a strong connection to his former apprentice, however, and cloned him in an attempt to rekindle their relationship; Starkiller's clone was the protagonist of "The Force Unleashed II."

Mara Jade

The future bride of Luke Skywalker was first introduced as his enemy in the Thrawn Trilogy by Timothy Zahn. The Force-sensitive assassin had worked under the command of Emperor Palpatine prior to his death, and in the wake of the New Republic's takeover, was forced to live as a smuggler. Although Grand Admiral Thrawn's campaign targeting criminals forced Mara to become an unwilling partner to Luke, the two eventually grew close as allies — and, later, lovers.

Luke helped Mara Jade put her dark past behind her and trained her as a Jedi, and she became one of the most prominent figures at the reformed Jedi Academy. Despite her hardened outlook, Mara Jade was compassionate and kind, and her experience with both sides of the Force helped other young Jedi refuse the temptations of the dark side.

Shortly after the remaining Imperial forces officially surrendered to the New Republic, Mara Jade and Luke were married and bore a son, Ben Skywalker. The two would go on to face other forces of evil throughout the Yuuzhan Vong invasion and the Dark Nest Crisis, but the most lethal threat came from within their own family. Mara Jade's death at the hands of her dark-side enabled nephew Jacen Solo was one of the most shocking and tragic moments in the entire Star Wars Expanded Universe.

Darth Plagueis

First hinted at during the iconic opera scene in "Revenge of the Sith," the Sith Lord Darth Plagueis was more than a legend. "The Tragedy of Darth Plagueis the Wise" that Palpatine tells Anakin is in fact a reworked version of how Palpatine killed his own master.

Plagueis was a member of the Munn species named Hego Damask II who worked as a magister of the InterGalactic Banking Clan — and as a secret Sith apprentice. After slaying his own master, Darth Tenebrous, Plagueis traveled to Naboo and recruited a young Palpatine, who was a shrewd politician only just discovering his Force capabilities. Plagueis trained Palpatine and transformed him into Darth Sidious, but his new apprentice's cruelty came as a shock even to the elder Sith. Plagueis and Sidious worked together to infiltrate the Galactic Republic after the Sith remained dormant for generations, but Plagueis didn't expect Sidious to cut him out of their plans.

Unbeknownst to Plagueis, Sidious had already begun training the young warrior Maul as an apprentice, and simultaneously planted seeds of the dark side in the Jedi Master Dooku. Although Sidious promised to make Plagueis his co-ruler upon winning the election for Supreme Chancellor of the Galactic Republic, Sidious killed his master during the events of "The Phantom Menace."

Jacen And Jaina Solo

Although the Star Wars sequel trilogy introduced Kylo Ren as the offspring of Han Solo and Princess Leia, for over 20 years the Expanded Universe had different characters pegged as the next generation of the Skywalker bloodline. The twins Jacen and Jaina Solo grew up to train at the new Jedi Academy established by their uncle Luke Skywalker on Yavin IV.

Jacen and Jaina grew skilled with the Force, developing personalities similar to their parents; Jacen's cocky, hot-headed attitude was not dissimilar from his father's, and Jaina possessed the poignant professionalism of her mother. Both of their abilities were frequently tested, most notably during the invasion of the New Republic by the Yuuzhan Vong in the "New Jedi Order" novels. The biological species wreaked havoc across the galaxy and took countless lives, including that of Anakin, Jacen and Jaina's younger brother. The conflict culminated in a climactic final battle in which Jacen defeated the Yuuzhan Vong overlord.

However, his heroism was short-lived. Jacen went down the same path towards the dark side that his grandfather Anakin Skywalker did. Trained by the Sith acolyte Lumiya, Jacen became the Sith Lord Darth Caedus and, in an act of villainy, killed his aunt, Mara Jade Skywalker. Caedus' reign of terror ended when he perished at the hands of his sister during a lightsaber duel in the novel "Invincible."

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