Mossferatu is a frog monster that dwells within the depths of the Den of the Dwarves, feeding on the precious glowmoss found there with his lackeys, a Quayhorse and a Wharfhorse. He has green skin, long whiskers, and wears a long red cape worn around his neck with a brooch in a dignified manner. He walks upright, hopping about on a singular hind foot. In his hand, Mossferatu carries a sceptre topped with a conch shell. In order to get their hands on the glowmoss needed to explore the Beacon, the party journeys into the den to eradicate the amphibian and his minions. He attacks by breathing out flames or icy blasts, as well as exhaling a venomous mist at his opponents. In VII Reimagined, he is aided by a Toxic toad and an Overtoad.
Mossferatu's Japanese name and original English name are a combination of gama (がま,gama?), the Japanese word for "toad" and the Latin word deus, which means "god" or "deity". His English name is a combination of the words "moss" and "Nosferatu", a word synonymous with vampire.