A louse monster that can drain energy from any machinery with its mouth-like hands and occasion discharge them as an attack. When Count Dregon learned that Dex was participating in a band contest at the Cosmos Arcade, Count Dregon had Gork unleash the Blue-Fanged Louse to drain the power out of various objects. Dex detected Blue-Fanged Louse at the power plant and became Masked Rider to fight him. Dex managed to get overwhelmed by Blue-Fanged Louse even when Dex's Rider Kick energy is absorbed. When it absorbed the Masked Rider powers upon Gork's arrival, it was too much for the Blue-Fanged Louse enough to regress it to the size of a louse. This enabled Dex to get away on Magno. Upon hearing a suggestion from Gork, Dregon sent Blue-Fanged Louse and three Commandoids incognito as a band named "Battle Cry" at the Battle of the Bands contest. Battle Cry's music was causing immense tremors around the arcade. Dex discovered their true forms and cut the power enough for Blue-Fanged Louse and the Commandoids to escape. When Dex catches up to them, Blue-Fanged Louse assumes his true form and ends up attacking the city as it absorbs the energy attacks from the Spiderbase. Dex transforms and fights Blue-Fanged Louse. Upon discovering a flaw in Blue-Fanged Louse's ability, Dex then used a combination of the Rider Kick and the Electro Saber to cut off Blue-Fanged Louse's left arm before finishing him off with the Electro Saber. He fits the category of Gork's unit.