The helmet of Hades was, according to Greek mythology, a helmet that had the power to make invisible anyone who wore it.
He got his helmet in Titanomaquia: the confrontation lasted ten years, but at last Gea (Mother Earth) prophesied the victory for Zeus if it took for allies that Crono had confined to Tartarus. Thus, Zeus killed Campe, the prison guard of Tartarus, and after releasing the Cyclopes and the Hecatonquiros, strengthened them with divine food and drink. As a consequence of this act, the Cyclops gave the lightning to Zeus; Hades was given the helmet that made him invisible; and to Poseidon a trident. With these weapons, they managed to defeat the titans.
In another event of Greek mythology, the helmet of Hades was in possession of the nymphs who helped Perseus to kill Medusa. These lent the helmet to Perseo who used it to be able to approach the Gorgons and to be able to escape of them thanks to the power of invisibility that conferred to him.
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