Akkorokamui

Multiple variant etiologies appear in Ainu narratives. One tradition tells of a multi-legged terrestrial monster or spider that ravaged people; villagers petitioned Samaykur kamuy and Okikurmi to shrink it, then begged Repun Kamuy (a sea god) to take custody, after which the being was plunged into Funka Bay and transformed into an octopus-like sea kamuy. Another variant ties the creature’s origin to ritual/garment imagery (for example, an under-belt cast into the sea becoming a sea-being). These versions are presented as alternative mythic explanations rather than a single canonical origin.

Legendary descriptions depict Akkorokamui as an enormous octopus-shaped sea being with prominent tentacles or 'strings' (reflecting the Ainu morpheme at meaning 'string/strand'), often described as vividly red. Accounts emphasize extreme size in folklore (legendarily given as reaching the sweep of '1 chō' in some tellings) and report that it is large enough in narrative to swallow ships and whales; precise measurements vary among sources and retellings.

Folklore attributes maritime menace to Akkorokamui: it is said to capsize or swallow boats in legend, produce violent bubbling and frothing in the tides where it is present, and be visible at distance by a brilliant red coloration. As a named kamuy and nushi of a bay, it occupies a position within Ainu cosmology where other, stronger kamuy (e.g., Repun Kamuy) can be petitioned to restrain or transform it; some tales recount such interventions. These powers and interactions are reported as elements of traditional narrative rather than empirically verified phenomena.