10 Stargate Characters Who Vanished Without A Trace
7. Haikon
Haikon was originally a leader in the Sodan, a group of rebel Jaffa warriors who rose up against their System Lord over five thousand years prior to their discovery by SG-1. Teal'c was well aware of them, though had never met a member. They existed by surviving on Goa'uld Symbionts stolen from Jaffa who still remained loyal to their gods, though this caused their numbers to dwindle over the years.
Haikon came to believe that the real gods were never the Goa'uld, rather they were the Ancients who existed millennia before them. Thus, he led the Sodan into converting to Origin. While this could have been a devastating blow, Mitchell and Teal'c were able to convince him that the Ori were no better than the Goa'uld he had served beforehand. He agreed to help SG-1 defend Earth against an Ori plague.
In retaliation, the Ori caused one of the Sodan, Volnek, to go mad and apparently die, only to be resurrected. This undead warrior then slaughtered a village, leaving only Haikon alive, though his symbiont was killed. SG-1 saved him by providing him with Tretonin but, after this, he was never heard from again. despite being a valuable asset for SG-1 and the Free Jaffa.