What monster did heracles kill?

Heracles, also known as Hercules in Roman mythology, famously killed the Nemean Lion, one of his Twelve Labors. The lion was known for its impenetrable skin and terrorized the region of Nemea. Heracles ultimately defeated it by strangling it with his bare hands, and he later used its own claws to skin it, wearing its hide as armor. This victory marked the beginning of his legendary feats.