Origin

Gunbor was the master mercenary of Helium and taught others the skill. When his star pupil Tok Nur was murdered by Mortus, he went to investigate the legend of Mortus himself, disguising himself as Raf Nek. Dejah Thoris stowed away on his vessel to Zodanga, but she helped him expose Mortus. Upon entering Mortus' hideout, he was captured and transformed into one of the Machine Men. When Dejah Thoris almost underwent the same surgical treatment as Gunbor, he regained his free will and helped destroy several Machine Men, but was ultimately killed himself.