Jysella Horn

Around 16 ABY, Jysella entered the world. By 25 ABY, she was a student learning at the Jedi Praxeum situated on Yavin 4, having spent more of her formative years in training there than living with her mother and father.

Following the attack by the Yuuzhan Vong on Yavin, Jysella resided for several months aboard the Errant Venture, the vessel of her grandfather Booster Terrik, together with her family. Later, she was relocated to the Shelter base located in the Maw along with the other Jedi younglings. When the Yuuzhan Vong War concluded, she remained classified among the younglings, yet she joined numerous Jedi who congregated for the Jedi conclave that took place on Zonama Sekot.

By 40 ABY, Jysella had achieved the rank of Jedi Knight and was actively serving. As the relationship between Corellia and the Galactic Alliance deteriorated, leading to an interstellar crisis, Luke Skywalker strategically assigned her to a distant mission, far from her homeworld, to prevent a conflict of loyalties when the Jedi were summoned to act as Alliance commandos and starfighter pilots during Operation Roundabout and subsequent operations.

In 43.5 ABY, Jysella became the third known Jedi to fall victim to the perplexing Force psychosis, a condition that had previously affected her older brother, Valin, and Jedi Knight Seff Hellin. While trying to gain insight into the ailment with Master Cilghal, Jysella experienced a sudden mental break, perceiving the Master as an imposter. Unlike her brother, who was consumed by intense anger, she was driven by fear. Jysella attempted to flee the temple, and while assessing the situation, she unintentionally flow-walked into the future, foreseeing her escape route. This knowledge enabled her to pinpoint the concealed locations of the secret security droids at the Temple's entrance, which she swiftly disabled.

Jysella persisted in her flight from the Temple, using the Force to hurl pedestrians aside and screaming in terror that those she knew intimately were not who they appeared to be. Two of her closest friends, Bazel Warv and Yaqeel Saav'etu, who had also been Valin's best friends, arrived at the scene and promptly tried to restrain her upon realizing her affliction. The two Jedi failed to stop her, and Jysella was ultimately apprehended by GA security. The entire episode was documented by journalist Javis Tyrr. Chief of Staff Natasi Daala arrived shortly afterward and addressed the gathered crowd, announcing that Jysella was now under GA jurisdiction and would be frozen in carbonite alongside her older brother.

When a group of Jedi presented a court-approved document permitting them to visit the carbonite-frozen Horn children, the group, accompanied by the press, discovered the two Jedi on display above an aquarium in the main office lobby of the Galactic Justice Center. Even with the Horns still frozen, Daala intensified her crackdown on the Jedi. Bazeel and Yaqeel succumbed to psychosis and were captured by the Solos and Jagged Fel. However, before GAS could apprehend them, Jagged Fell and the Solos managed to spirit them away. Subsequently, three more sheltered knights, Sothias Saar, Kunar Baan, and Turi Altamik, fell ill. When the Acting Grand Master refused to surrender Sothias and Turi (Kunar had been apprehended in the temple, so Daala was unaware of him) into Alliance custody, Daala dispatched a battalion of Mandalorian soldiers and vehicles to blockade the temple. A day later, after the psychotic knights had recovered from the illness, thanks to the indirect efforts of Luke Skywalker, Ben Skywalker, and a fleet of Sith, Daala publicly agreed to lift the siege but refused to release Valin and Jysella until she was convinced that the Jedi would conceal nothing from her.

Acting Grand Master Kenth Hamner attempted to prevent the Jedi Order from taking any action to free the kids, as it would invalidate his clandestine, unsanctioned agreement with Admiral Nek Bwua'tu. The entire Council was indignant at Kenth, particularly Corran Horn, the father of Valin and Jysella, for the Grand Master's allowing his children to remain at Daala's mercy, accusing him of stalling. Later, Daala contracted a company of Mandalorians to 'put down' a gathering of pacifist Octusi servants on Blaudu Sextus, resulting in a brutal massacre.

After waiting impatiently for the opportunity to launch their StealthXs, due to Grand Master Kenth Hamner's attempts to buy time for Admiral Bwua'tu to awaken, they informed him that they had to launch now, before it was too late, but he still refused them. Eventually, Han Solo compelled him to reveal his deal with Bwaatu, and the entire Council stripped him of his title and confined him to his quarters. Luke secretly requested backup from Ben at the Temple on the Moon of Pydyr to confront Abeloth and the Lost Tribe. To that end, the Jedi devised a plan to both reinforce the Skywalkers and rescue Jysella and Valin.

Their grandfather, Booster Terrick, brought the Errant Venture into Coruscant's orbit to host a sabacc tournament, with dozens of political and social elites, including Chief of Staff Wynn Dorvan, participating in the fifty-million credit prize sabacc tournament. Booster began firing on Coruscant's climate control system and diverted the Galactic Alliance Fleet's attention long enough to give the Jedi a chance to launch their StealthX strike team without a shot being fired. Amidst the chaos, Jaina, Leia, and Han Solo led another strike team consisting of Zekk, Terran Zel, and many of the recently recovered knights to breach the GA detention center and retrieve the Horn siblings' carbonite pods. With the Jedi StealthX fleet gone, the Horns lost, and Imperial Head of State Fel withdrawing from negotiations with the Galactic Alliance, GA Chief of State Daala had lost all of her leverage against the Jedi Order and was publicly humiliated. Soon, Corran and Mirax were present when Cilghal unfroze the kids from carbonite.

Unbeknownst to the Jedi at the time, the Horn siblings were still affected by the Force illness they had suffered from before they were frozen. While the Jedi were distracted storming the Senate and capturing Chief of State Daala, Jysella and Valin Horn enlisted the aid of journalist Kandra Nilitz in getting them to Nam Chorios and destroying their trackers in exchange for an exclusive news story.

During an online chat session (and thus not considered canon), Michael A. Stackpole disclosed that Jysella Horn was named after her maternal grandmother, Jysella Terrik. This information was subsequently confirmed and integrated into canon in the Scum and Villainy sourcebook published by Wizards of the Coast, where her maternal grandmother is named.

Jysella's age is not precisely defined within canon; however, her absence from Specter of the Past, Vision of the Future, or Star Wars: Union suggests that she was born no earlier than 19 ABY. In fan fiction, she is frequently portrayed as being closer in age to her brother Valin than canon suggests, leading many fans to believe that she is older than she is. Conversely, some fans have underestimated her possible age range, placing her birth closer to 25 ABY than is implied by her introduction in The New Jedi Order: Dark Tide I: Onslaught.

The preview located at the end of the novel Fate of the Jedi: Outcast contains an excerpt from the upcoming novel Fate of the Jedi: Omen, which features Jysella as a significant character. The preview, written from Jysella's perspective, states that Jysella is ten years younger than Valin, placing her birth year around 23 ABY. However, upon the release of Fate of the Jedi: Omen, this information was revised to three standard years, shifting Jysella's birth year to approximately 16 ABY.

On page 362 of the hardcover edition of Fate of the Jedi: Vortex, her name is incorrectly spelled as "Jysell Horn".