Battle of Ossus (Great Sith War)

The Battle of Ossus took place in the year 3,996 BBY, near the end of the Great Sith War.

During the Battle of Kemplex IX, a sabotaged ancient Sith device used to manipulate matter within the cores of stars caused the detonation of the nearby Cron Cluster stellar group, triggering a massive supernova shockwave in whose direct path lay the Jedi training world of Ossus.

A large-scale planetary evacuation was called, with civilian and Jedi personnel alike struggling to escape the planet before the nova-wave arrived. The Jedi Masters planetside began a rescue operation focused upon salvaging as many relics, manuscripts, and other antiquities as possible from the enclave, lest time run out. This would, in part, prove to be too tempting an opportunity for Exar Kun to pass up. Linking up with fellow Sith Lord Ulic Qel-Droma and reinforcements of Mandalorian and Massassi warriors (redirecting Lord Mandalore the Indomitable's main battle groups to Onderon), Kun launched a raid upon Ossus itself, intent on looting vast quantities of Jedi knowledge for his own personal vainglory.

With the evacuation already reaching critical levels, the Sith and Mandalorian ships converged upon the planet, targetting numerous civilian and military transport craft, engaging the Jedi defenses long enough for Kun to slip beneath the screens and land in the enclave. Among his first targets of choice was the residence of Master Ood Bnar, himself attempting to preserve a cache of antique Jedi lightsabers against the oncoming destruction. Engaging Kun and his Massassi, Master Bnar realized that his true skills lay not in combat, but in the powers of the Force itself. Drawing upon it, Ood turned himself into a great tree, derailing Kun's plan to steal the weapons.

Not far afield, the Cathar Jedi Sylvar assaulted Kun near his ship, seeking revenge for her mate Crado's death at Kemplex IX, but was beaten down by his elite Massassi guard. Cay Qel-Droma, however, sensed his brother Ulic's presence amongst the battling orbital and sub-orbital ships, and took the Nebulon Ranger to the skies in an effort to sway Ulic back to the light. Shot down by Mandalorian ships during the melée, Cay was forced to crash-land in the city, where the two brothers confronted each other for the very last time. Attempting to reason with him, Cay only succeeded in provoking Ulic's temper - the Dark Side surging within him, Ulic insitgated a violent lightsaber duel, shearing off his younger brother's mechanical arm. Pleading with him, Cay tried to reach through to the Jedi deep beneath Ulic...but in one final surge of anger, Ulic slew his brother where he knelt.

As a final act of punishment and retribution, Nomi Sunrider imprisoned Ulic beneath a wall of Light Side Force-energy, forever cutting him off from that mystical field. The stage would now be set for the final showdown with Exar Kun at Yavin IV and elsewhere.