Leo had to do with the labors of Heracles. On his first task, he was sent to kill the Nemean Lion. This lion was savage and fearless as he couldn't be harmed by weapons. After attempting to kill the lion with arrows, which just bounced right off, Heracles wrestled the lion and strangled it to death. He didn't go away unharmed, though; the lion managed to bite off one of Heracles' fingers. After the lion was dead, Heracles skinned it with it's own claws and made some wonderful armor from the pelt and jaw. The constellation Leo is said to honor the bravery of battle between the Nemean Lion and Heracles.