What was Hades the God of? What was Osiris the God of? Is there any overlap between #1 and #2?
Underworld
Hades was the Greek god of death and the Underworld. Osiris was the Egyptian god of the Underworld.
The mythic Relm of the Dead, located far underground (aka, Hades; Underworld)
Would Hades and Osiris hypothetically compete for real estate in the Underworld?