Prometheus decided to steal fire from Hephaestus and give it to mankind to help them survive. When Zeus discovered this, he had Prometheus chained to a rock where an eagle would eat his regenerating liver as punishment. Prometheus endured this torture for thirty years until being freed by Hercules. Zeus also punished humans by having Hephaestus create Pandora and giving her a box containing all illnesses and evils, which she opened out of curiosity, unleashing these upon humanity.