Cerberusmon

Cerberumon is a Dark Animal Digimon whose name and design are derived from the mythological Cerberus. It is called the "Watchdog of Hell". The claws on its feet are hard enough to easily tear through Chrome Digizoid alloys, if they have a low purity. Also, its body is protected by a hard living shell, which has the ability to instantly repair any damage it incurs. The armor on its shoulders each possess sentience, and are able to instantly sense an attack coming from any direction, then report it to Cerberumon's central body.

Digimon Frontier
Cerberumon is one of Cherubimon's servants, sent to the Flame Terminal to find a Spirit. He ravages the Terminal and attacks Takuya, only for the H Spirit of Flame to be revealed. Cerberumon attempts to take the Spirit for himself, but the Spirit chooses Takuya instead, allowing him to spirit evolve to Agunimon. After a tough battle, Cerberumon is defeated, his Fractal Code scanned and purified by Takuya's D-Tector. All Aboard

Attacks
 * Portals of Darkness (Inferno Gate): Opens a "Hell Gate" engraved in the earth, then casts the opponent through it to the jet-black Dark Area.
 * Emerald Blaze (Hellfire): Spews a green jet of flames.

Role in Ultima
In Ultima, Cerberumon is.