Big Kahuna Island was an island on Mobius located near the Devil's Gulag and was home to West Robotropolis. It was used as a secret base by Snively and a group of other convicts after their escape from the Devil's Gulag. Sonic the Hedgehog and members of the Royal Secret Service traveled to Big Kahuna Island via a submarine to retrieve Nate Morgan, who had been captured by Snively and his goons. It also turned out that the underside of the island was the resting place of a giant squid Mutate that was brought out of dormancy when one of Robo-Robotnik's satellites orbiting overhead reactivated, broke through the surface, and caused even more damage to the already ruined structures. (StH: #68, #70)