Ambush in the Ansharii Caverns

The Ambush in the Ansharii Caverns took place in c. 3,996 BBY on the planet of Toprawa, shortly after the Sith War battle that took place there. The ambush was orchestrated by the smuggler and bounty hunter Dossa, who was allied with the Sith. Attempting to lead Jedi failure Haazen and Barrison Draay into a trap, the Nautolan implanted a bomb within the caverns. Although Haazen was aware of the bomb, he did not know that Dossa was planning to betray him; he thought the trap was meant only for Barrison, of whom he was jealous and wanted dead. After leading Barrison and his team of Jedi into the caverns, telling them that the last Sith base on Toprawa was there, as well as Dossa. Haazen ran on ahead to alert Dossa that the Jedi were coming, but the smuggler chose that moment to detonate the bomb before Haazen could get out of range. The resulting explosion killed Barrison and the other Jedi immediately, but, since he was not caught by the brunt of the blast, Haazen survived and instead suffered massive injuries. Dossa then brought him to Doctor Uburlah, a Massassi with a knowledge of prosthetics and Sith equipment. He applied a prosthetic eye and limbs to the now severly disfigured Haazen, implanting several Sith objects onto him as well to give him extra strength. When he awoke, Haazen was outraged, as his fake limbs weren't human prosthetics and he knew he looked horrific.

It was this event that caused Haazen to embrace the dark side, and he killed Dossa and possibly Doctor Uburlah before leaving the caverns.