E. magnificus bears the distinctive characteristics of the genus Enteroctopus, including longitudinal folds on the body and large, paddle-like papillae.

E. magnificus is a large octopus, reaching total lengths of up to 1.8 metres (5 ft 11 in)[1] and a mass of 11.4 kilograms (25 lb).

It is found primarily on sand and mud flats from shallow subtidal areas to about 1,000 metres (3,300 ft) depth.

The chief food source for this octopus is the deep-sea portunid crab Bathynectes piperitus.

Harvest of this octopus is small, mainly as a finfish trawl fisheries by-catch.