History
Professor Shecktor was heading the research into developing a universal snake venom antidote, with Klaus Voorhees as his assistant. Klaus turned on his boss and killed him with a cobra and tried to hide it by getting bit and curing himself. However, he did not realize that Shecktor had been experimenting with radioactivity and became the Cobra. On his deathbed Shecktor wished for Thor's aid in defeating the Cobra.[1]