Stricken with grief over the loss of Iolaus, Hercules vowed to bring him back from the Sumerian version of the Underworld. Nebula, who confessed her love for Iolaus in his final moments, accompanied Hercules on his journey. The son of Zeus rappelled down into a cave to confront Dumuzi, the Sumerian god of the Underworld. Dumzumi had been collecting human souls in order to survive, ever since King Gilgamesh had destroyed the sacred chalice. But Iolaus had already crossed over to the Underworld and was lost forever. Hercules' cry of rage shattered the mirrors surrounding Dumuzi's lair, destroying the god.