Aurum was the main character in Nature, and the leader of the robots in Chromium City. In an attempt to "take back what was his" he ended up being killed by the Sun God, Heliora.
Aurum was the 'robo-son' of Tonitrui and Fulgur. He had a very troubled childhood; no-one wanted to be his friend or 'hang out' with him. Once he turned eighteen years of age, however, he joined the Motor Drivers, a band of outcasts seeking power and fame. The adult bots thought this gang was all child's play and such, but once it had been discovered that they had murdered a robot known as Hostia, they were all sent to prison.
It was then that Aurum discovered his ability to grip and crush objects with his metal hands. He broke out (leaving the others behind) and tripped over a screwdriver on the ground, denting his head and knocking him unconscious. When he woke up, he couldn't remember a thing about his past self.
After several days of hospitalisation, he was eventually let out, and he decided to become a model citizen. These actions led him to become the leader of his hometown, and he was just about to make peace with another city when he received the news that one of the neighbouring nations had been taken over by the sun god, Heliora. Equipped with his strong arms, he went to fight.
Aurum set off on a long, difficult quest, joined by follower Argentum. Along his way, he got knocked out by an imp in Earthdrop Canyon. Although it didn't show at first, he had reverted to his old, ruthless self and showed no remorse. Eventually, he was defeated at the hands of Heliora, who was distraught at the loss of her daughter Flumen.
Aurum had the strongest arms out of all the bots in the city, and originally used them to steal money from banks or brutally injure people so that he could get his face in the paper, but after his nasty accident, he started using it for crushing metal beams in construction work. During his quest to stop Heliora, he picked up many abilities stolen from Heliora's creations that were created to stop him. This allowed him to manipulate the earth, spit seeds and other crazy stuff no-one else of his caliber could pull off.