Ocean Octorok

Ocean Octoroks are a type of Octorok. As their name suggests, they are solely found in the sea. They are based off the sea-living iteration of Octoroks from The Legend of Zelda: The Wind Waker, though are in games where normal Octoroks are land-based. Like the versions from The Wind Waker, they are quite large, appearing at a comparable size to the player's vehicle.

The Legend of Zelda: Phantom Hourglass
In The Legend of Zelda: Phantom Hourglass, Ocean Octoroks are a common enemy in the segments aboard Linebeck's ship. They have a pink body and a yellow shell on their back with a purple swirl design on it. They surface before following the ship along from the front, and unless shot with the cannon, will attack the ship with their own projectiles.

The Legend of Zelda: Spirit Tracks
In The Legend of Zelda: Spirit Tracks, Ocean Octoroks are limited to the Ocean Realm, where they are only found in the underwater series of tracks. This time, they have an orange body and tend to move in a circular pattern due to no longer being limited to horizontal movement.