|Family and Relations||Unknown|
|First Appearance||Great Mazinger (Manga)|
Gratonios is a humanoid Warrior Beast with a mainly light and dark purple body. Its head has a light colored face with sharp teeth and a dark colored helmet with spikes and horns extending out of the helmet. Its pectorals feature a pair of faces resembling white and purple masks. Its hands are replaced with drills.
Gratonios is capable of short flight, its drill hands can extend for a short distance which is useful in close combat. The faces on its pectorals can act as shields and can shoot beams that can cause explosions from the eye sockets. Gratonios can also release electric shocks from the horns on its head.