In Greek mythology the Nemean Lion was a fearsome beast slain by Hercules* as one of his 12 Labors. The hero had killed his wife and children in a fit of madness and was told by an oracle to go to the city of Tiryns for his punishment. There King Eurystheus could present him with 12 seemingly impossible challenges or labors.
Hercules' first task was to slay the Nemean Lion, the offspring of the monsters Typhon and Echidna. Twice as large as a normal lion, the animal had skin so tough that no weapons could penetrate it. After tracking the lion to its cave in the land of Nemea, Hercules tried to kill it with arrows given to him by the god Apollo*. However, the arrows simply bounced off the lion. Hercules struggled with the beast using only his bare hands and strangled it to death. He then used the lion's own razor-sharp claws to remove its skin. Afterward, he wore the skin as a cloak to make him invulnerable.
oracle priest or priestess or other creature through whom a god is believed to speak; also the location (such as a shrine) where such words are spoken
invulnerable incapable of being hurt
After killing the beast, Hercules took the skin back to Eurystheus, but the king was so terrified when he saw the lion that he hid himself inside a storage jar. He told Hercules that, from then on, the hero should present his trophies to a messenger outside the city To honor the lion's struggle against Hercules, Zeus* (or Hera* in some accounts) transformed the lion into the constellation, or group of stars, called Leo.