amjnyard:

Athena, the goddess of wisdom and military victory, and also the patron of the city of Athens, was Hercules’ half-sister. Her parents were Zeus and Metis, a nymph. Zeus heard a prophecy that the child Metis bore after she gave birth to Athena would become the lord of heaven, so, to prevent this from happening, he swallowed Metis while she was still pregnant with Athena.

When the time came for Athena to be born, the smith god, Hephaistos, opened Zeus’ head with an axe, and Athena stepped out, in full armor.