Ok, I should explain this, as I have gradually done on XWA:
Deac Starkiller was a rebel agent who was abducted and pumped full of midi-chlorians to become a jedi by the empire, but escaped along with his evil cousin Syrnl Darkstar.
Ancient prophecies from another dimension tell of how one being who fights for good (The Starkiller) would be in constant battle with the evil opposite, (The Darkstar) throughout time and space. These beings would chose and inhabit mortal beings in the form of swords. Deac is the good one.
Hope that clears it up! For more info, look up the old "Cantina Scenario" threads in XWA's RPG forum!
Deac: Purveyor of Fine Quality Postage Since 2001