After the trial, Sylvar traveled with Jedi Knight Nomi Sunrider, her daughter Vima, and Jedi Master Thon to the planet of Ambria for healing and perhaps some more training. However, even their quest for solitude on the remote planet of Ambria was interrupted by Jedi Knight Oss Wilum, Thon's former student, and Sylvar's mate, Crado, both under Kun's Sith spell. Summoning the dark side beasts of Lake Natth, Oss and Crado sent them to attack Sylvar, Thon, and Nomi. Following the beasts, Oss and Crado joined them as they attacked the Jedi. Sylvar, Nomi, and Thon were easily able to deal with the reptilian beasts, but Oss and Crado were another story. During the fray, Sylvar gave Crado a wound on his face not unlike the one she gave Exar Kun not long before.

The Jedi were able to subdue Oss Wilum and use the Light Side to awaken him from the influence of the Sith spell, but Crado managed to escape to his ship and retreat back to the safety of the Krath fleet. Sylvar's despair was now complete as she realized Crado was too easily controlled by Kun, and finally accepted that she had lost him forever. Realizing the attack on Thon and the Jedi was not unique and was part of a plan to murder many Jedi Masters, Sylvar, Thon, and Nomi returned to Ossus hoping that any other Jedi Masters were as fortunate as they had been. Once having arrived on Ossus, Sylvar and the Jedi learned that the Krath was mobilizing in the Auril Sector near the Cron cluster, a system of ten unstable stars, and a team of Jedi was sent there to deal with the fleet. Sylvar remained on Ossus, when Ulic, Exar Kun, and an army of Mandalorian warriors attacked the planet.

An evacuation of Ossus was called for, and Sylvar and the Jedi soon went to work trying to save as many Jedi artifacts and texts as possible. Learning that Exar Kun was on Ossus, Sylvar left to confront him to deliver the justice she felt he deserved. Cutting her way through countless Massassi warriors, Sylvar was unable to reach Kun before he retreated in his ship to the jungle moon of Yavin IV, having acquired what he came for. However, from the Auril Sector, the Krath used ancient Sith magic to rip the core of one of the stars in order to kill the team of Jedi sent there. However, a chain reaction was started resulting in all of the stars of the Cron Cluster going supernova destroying the rest of the Krath fleet, which included the Sith ship Sylvar's mate Crado had been on.

The explosion of ten suns sent a supernova across the galaxy, one that was headed straight for the Jedi planet of Ossus. With the attack subsiding, Sylvar returned with the rest of the Jedi of saving as much as possible from the Jedi library there. As the supernova drew closer, so did the end of the war. Ulic Qel-Droma was finally defeated on Ossus when he finally realized the horrible things he had done, which included the murder of his own brother Cay Qel-Droma; on Onderon, the rest of the Mandalorian's army was being dealt with by the beast-riding army of Modon Kira. When the time came for ground zero, Sylvar and the rest of the Jedi left Ossus to the mercy of the shockwave.