The Squid Mutant is an agent of Gorgom. It can attack with its tentacles, shoot purple beams from the side of its head, and shoot a smokescreen from its mouth.
Baraom was after Rana Kauai so Gorgom can use her powers to help them since the women of Kauai, Hawaii are said to have untapped powers. Kamen Rider Black fought Squid Mutant when it tried to "abduct" Rana and was unexpectedly joined in fighting this monster by Ryusuke Taki.
In the second battle, Baraom had Rana attack Kamen Rider Black during his fight with Squid Mutant until Bilgenia interfered to attack Kamen Rider Black. Taki fought Squid Mutant when Baraom and Bishium found Rana and ended up shooting off one of Squid Mutant's tentacles. After fighting Bilgenia, Kamen Rider BLACK joined the battle and saved Taki. He fought Squid Mutant, Baraom, and Bishium until Darom appeared to help. Once again, Baraom took control of Rana and had her attack Kamen Rider Black. Taki was able to break the pendant that Baraom was using to control Rana. This gave Kamen Rider Black the advantage and he kill Squid Mutant with the Rider Kick.