The colonies of Clava multicornis are unique among the Hydractiniidae because they live in the intertidal zone and are adapted to withstand exposure to the air for extended periods. The polyps of this species are conspicuous and easy to find among the mats of brown algae, where they form bright pink/orange colonies that cannot be mistaken for any other species of hydrozoan. Clava multicornis is known in Norwegian as tangkøllepolypp or tangblomst, in reference to its habit of growing on brown algae from the littoral zone (tang).
