The grand duke of Hades is a very powerful demon, he orders 90 infernal legions. He is the brother of Zeus and son of the mighty god Cronus with Rhea goddess, it is believed that the Greek gods are the Anunnaki who took the land for human control, some rebel gods perished to the lower underworld also known as hell during the gods' war.
Hades is regarded as the commander of the dead to his great army to destroy the temple of his brother Zeus, along with their gods allies. In the story about Hades, he was the younger brother of Zeus, who was jealous of his brother that he had defeated his father Kronos, when he became a marine beast that devoured his other brothers: Hestia, Demeter, Hera, Hades, Poseidon. Reia sacrificed unsuccessfully trying to save Zeus Cronus, Zeus grew up, he decided to take revenge of his father, asking for that made the support of Métis - Prudence - daughter of the Ocean Titan. This gave Cronos a magic potion that made him vomit the children who had eaten.
So Zeus became lord of heaven and supreme deity of the third generation of gods from Greek mythology to banish the Titans to Tartarus and pulled his father's throne, and according to Homer's words arrested him with chains in the underworld, where he was found, after ten years of bitter struggle, for their brothers the titans, who had thought could regain power from Zeus and the gods of Olympus.
Hades with his jealousy for Zeus, joined Hera for a war with Zeus and try to destroy his temple with his Titans brothers, Hades and Hera were defeated and thrown into the underworld of hell, they had separate and different destinations, Hades controls two worlds creating demons and ruler of the dead, in order to offend the titans and their opponents.