While the Army was fielding its own walkers, the CGU Marines were left out. Tests done with modified marine-type Wolf mechs were unsatisfactory. To this end, the Marines ordered an amphibious field walker, capable of moving underwater and attack on land, to augment their ageing arsenal of amphibious mecha. This produced the Sealion Amphibious Walker, a rugged, sturdy mechanised walker armed to the teeth for oceanic and amphibious warfare. Designed with a more organic and streamlined shape, the Sealion also integrated hydro-jets for greater underwater speed, and a pair of high-output water-cooled reactor to power the directed-energy weapons mounted in detachable, wire-guided arms. Deployed in the late 4290's, the Sealion became valuable to Marine operations in retaking CGU outer colonies with heavy ocean cover, and again in the campaign to take the Zaaroft inner colonies.
Height: 14 meters
Dry Weight: 15 tons
Full Weight: 33 tons
Accommodation: 1 pilot, cockpit in upper torso
Armour Materials: boron nitride with diamond coating
Powerplant: 2 x ultracompact nuclear reactors; 2 x T400 turbines
Power output: 1250 kilowatts each
Fixed Armaments: 2 x 20mm rotary cannons, mounted in head; 2 x 30mm automatic cannons, mounted in torso; 2 x 36 KW Phonon Masers, mounted in hands; 2 x Retractable 10-cell Rocket-Assisted Light Torpedoes, mounted in shoulders.
Optional Armaments: MM-71A1 50mm automatic rifle, 100-round drum; Mark 66 320mm recoilless rocket launcher; Mark 70 533mm torpedo launcher.