The description of the mythological Kraken, which lives deep down at the oceanbed in the frigid coastal seas of Norway and Greenland, has some contradiction in it. Some descriptions emphasize that it is octopus-like while others emphasize that it is more crab-like. It may be a bit confusing to try to mentally combine these two very different images.
All descriptions agree that the Kraken (meaning twisted animal in Old Norse) is a giant creature that lives at the ocean bottom. It is said to feed on schools fish for up to three months, digest for up to another three months, then rise to the surface with a vast disturbance of the waters that extends for miles and seems like the eruption of an underground volcano.
Drawings usually show a massive head cum body with massively extending octopus tentacles that rise up and out in twisted undulating motions (twisted creature?) grabbing at all desirable things nearby. If the crab version is preferred, I suppose that would mean a hard flattened head and body instead of a domed soft-tissue head and body, with crab-like clappers at the ends of the tentacles instead of octopus-like suction-cup covered tentacles that terminate in a point. [Be sure to click the image below to enlarge it as only the top half shows.]