Nemean Lion, in Greek Mythology, was a creature that inhabited the plain of Nemeia, in Argolis, where he terrified the whole region.
The terrible beast could not be killed by a normal man for having leather of impenetrable material for mortals (humans) and everyone who tried to face it was completely terrified by its roar, which could be heard from miles away. Furthermore, no weapon could penetrate the animal's leather! Everyone who tried to kill him with spears or arrows ended up being devoured.
The origin of the Lion of Nemea is controversial. According to some versions, they are the result of the union of Equidna and her own son Ortros, the two-headed dog. Another version is that he would be the son of Cerberus with Chimera, and therefore grandson of Typhon and Echidna.
However, we are starting from the most known and accepted version, where the Lion would be the son of Typhon and Echidna.