Demagol, born Antos Wyrick, was a male Zeltron scientist who joined the Neo-Crusaders during the Mandalorian Wars. During his childhood, Wyrick was captured by Iskalloni slavers from whom he learned his infamous surgical techniques. Subsequently released by a Mandalorian raid, the young Zeltron was taken into Mando'ade culture and trained in martial arts by Mandalore the Indomitable himself. In 3996 BBY, after the Duel on Kuar and the victory of Ulic Qel-Droma over Mandalore, Wyrick became fascinated by the Force and its mechanisms. Having stolen the robe of the Arkanian Jedi Master Arca Jeth in Ulic's affairs during the Great Sith War, the scientist began experimenting with a hair found in the clothes of the disappeared master at the end of the war.
After the war, Wyrick became engaged to a Zeltron woman and had a child with her, whom they named Chantique. He was also the master of a mysterious school on Osadia, in which Chantique and Edessa were pupils. When the school was destroyed by the Crucible, Wyrick was crushed. Wyrick later became a Mandalorian Neo-Crusader, under the alias of Doctor Demagol, and served as Mandalore the Ultimate's lieutenant with Cassus Fett during the Mandalorian Wars. After the capture of Flashpoint Station by the Mandalorians, all Jedi prisoners were sent there to be studied by Demagol, in hopes of finding the secret of their powers to negate and/or replicate them, not understanding the complexity of the Force.
When Zayne Carrick, a fugitive Jedi Padawan, arrived at Flashpoint intending to free Jarael, as well as the Jedi there, Demagol switched armor with Mandalorian Rohlan Dyre, whom he drugged in a coma, and joined Carrick under this guise. Dyre, falling into a coma, was transferred to Coruscant. Demagol traveled with Carrick and his crew, showing an interest in Jarael, whom he believed was actually Edessa. Eventually Jarael left Carrick's company, and Demagol followed her, revealing his true identity. At the same time, Dyre awoke on Coruscant and the identity-switch was discovered by Carrick and his friend Marn Hierogryph.