These lords of the Otherworld preside over the mystical realms to which heroes pass after they die. Once in a while, they come across a mortal that wanders into their kingdoms—and those humans only sometimes return to their homes. Manannán is the master of the Irish Otherworld, one of the most blissful places in the world.
This Norse deity rules over Valhalla, the paradise where deceased heroes hang out after they kick the bucket. It's a gorgeous place where Odin and his friends can chug all the beer they want and eat boar meat everyday. Manannán and his Irish buddies sometimes come over for a drinking game or two.
Zeus's big brother keeps a tight rein on his realm of the dead in Greek mythology. Greece's greatest heroes, from Agamemnon to Achilles and beyond, head down here after they've said goodbye to the world above. They will hang out with each other, feast, and maybe even sport with a lady-spirit or two.
What do you if you get lost in the Underworld? Call your mom, of course. When the Finnish hero Lemminkäinen drowned in the Underworld's river, his mama wouldn't stop until she found his body. She went downstairs to the Underworld, knitted his body back together, and revived him. Since then, Lemmy dotes on his mom—just like every son should.
Dumuzi, a Sumerian god of vegetation and fertility, is familiar with the number one rule of all societies: Listen to your wife. When his wifey, the goddess Inanna, was ticked off that her hubby wasn't paying attention to her, she ordered that Dumuzi spend six months in the Underworld. Harsh, right? After kissing up to Inanna—with flowers, chocolates, and lots of diamonds—Dumuzi did finally get her to let him spend the other six months with her on Earth.