I'll be posting all the remaining Warrior Beast throughout the day, to be on par with the ones on DA - and maybe, you guys might get a new one before I post it on DA

Gravalus was a Mikene Empire Horse like Mammalian type Warrior Beast under the command of General Ligern on Episode 20 of the Great Mazinger series, and served as both an aerial attack unit and Troop carrying transport for the Army. Gravalus was one of the few Mammalian Warrior Beasts with the capability of flight, having 2 massive thrusters for fore and hind legs, with its wings providing stability in flight. His arsenal where explosive fireballs shoot from the wings and missiles fired from the back fin. His real face was located right under the neck.

In the episode, the Borot Gang discuss the means to come up with their own Radar system when a group of Scientists appear and graciously built one for them – unbeknownst to them are Mikene Agents in disguise, who built a jamming device that interferes with the radar of the Science Fortress, this in preparation for an assault using Gravalus who is then launched as the Borot Gang use the Phony Radar - when Tetsuya arrives to demand a seize and desist, Gravalus arrives and attacks the lab. When Tetsuya launches Great, the two fight have a brief fight, and Tetsuya dispatches him with the Breast Burner.

His only other appearance in the franchise is in Mazinkaiser vs the Great General of Darkness Deathmatch, during the hunt for Koji, Sayaka and Prof. Mori Mori in Siberia, appearing along with fellow Mammalian Warrior Beasts Mammothdon and Dolman, under the command of General Ligern, stopping Archduke Gorgon from killing Koji in order for the General to take the credit for himself. The General and his Warrior Beasts try to stop Koji and Sayaka from escaping on a jet, but were destroyed when Mori Mori sacrifices himself by unleashing the base's missile arsenal on them, with Gorgon been the sole survivor of the barrage. Gravalus in the OVA looked much the same, but was slicker with white, golden, silver and blue colors rather than the Red and Yellow in the Great series, and instead of red hair and beard in his human face it was fully white, and did not show the sharp teeth. The Horse's head looked smaller than his original counterpart.