Calypso was a nameless voodoo priestess, possibly of Haitian descent. She was a psychopathic woman who was associated with Sergei Kravinoff, aka Kraven the Hunter. Calypso seemed to enjoy driving Kraven into fits of rage and furthering his hatred of Spider-Man, which ultimately led to Kraven's suicide.
The explanation for Calypso's supernatural powers was the sacrifice of her younger sister. She used her abilities to hold Curt Connors, The Lizard, in her grasp, and the two nearly succeeded in murdering Spider-Man. However, the webslinger managed to best them both, and Calypso was apparently killed. Calypso soon returned, and retrieved the Lizard from The Vault so she could control him again. However, the enraged Lizard slashed her throat open and escaped.
Her voodoo preventing her from truly dying, Calypso returned again in Spectacular Spider-Man #251-253. Commanding a squad of savages, she attacked Spider-Man and Aloysha Kravinoff, the son of the original Kraven the Hunter. Desiring revenge for losing Sergei, she used her powers to drive Spidey and Aloysha into fighting each other. Spidey and Aloysha fought off her spell, and shared a handshake. Aloysha said that he would hold Calypso at his mansion, so the villainess could tell him about his long-lost father. However, Aloysha slew Calypso instead.
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