Who is the Greek god of the underworld?

The story behind the answer

Hades is the Greek god who rules the underworld, the realm of the dead. After the Olympians defeated the Titans, the three brothers drew lots: Zeus took the sky, Poseidon the sea, and Hades the underworld; Apollo is a god of music, prophecy, and the sun, not death’s domain.

Hades isn’t evil—he’s a stern keeper of order, guarding souls (with Cerberus) and the riches beneath the earth; his name can mean