The Octo Cave, located on the same landmass as Mahri Nui, was the source of Kalmah's sea squid, which plagued the Matoran of Mahri Nui for a long time. Kalmah came here frequently.1
Notes
It was also called the Squid Cave. This was the breeding ground for the deadly squid used by the Barraki as weapons. Here Kalmah watched over the hatchery and saw to it that the squid were raised in such a way that their natural ferocity would be increased.2