Robo Hooves is another of the experiments from the private mining company, Blackbone. This time they decided to use a "worthless, disposable pony." Who he was before his 'transformation' is a mystery to him; most of the memories of himself lost. All he can remember of his identity is that his talent was related to technology. He too escaped from Blackbone's laboratories and made his way back to Equestria. Fearing the reactions of other ponies to his mechanical body, he wanders the outskirts of Equestria.
Armed with an Energy Sword designed by Blackbone for slicing through rock to dig, he awaits the day they come for him. It's not a matter of 'if', but 'when'.