He was voiced by Crispin Freeman
Gus Grav started as an adversary to Dan and his friends when he tries to capture Drago, but he failed twice. He later betrays King Zenoheld to reform, he was captured by King Zenoheld along with Vulcan after Elico sacrifices his own life to protect him from Fabros' deadly attacks. But he and Vulcan survive after being sent to prison, but he and Vulcan manage to escape from prison to get revenge on King Zenoheld for killing Elico and Hexados.
After defeating King Zenoheld, he, Vulcan, Drago and their friends including Dan and their friends managed to escape from the Alternative who is about to explode, causing King Zenoheld to die along with Prince Hydron who betrays his father including Clay Fermin in a destruction of the Alternative, so Mira Fermin has never had to worry about her father again after this later watches the Gundalian Bakugans.
Gus Grav also appears in Bakugan Mechtanium Surge along with Vulcan, he was seen helping his friend Spectra and Helios saving the Earth from Mag Mel and the Chaos Bakugan. After Mag Mel and Razenoid's deaths, he was seen congratulating Dan and Drago and returning to the Vestal with Spectra.