Doctor Fate #2
Initially Helmet of Nabu was created as a repository of the spirit of Naboo. When a person is put on the artifact, Naboo is infused into his body and began to control his behavior. But over time, the spirit of forgotten how to manage own helmet and now can only give advice. You can safely say that the helmet of Nabu is one of the most powerful artifacts in the universe. It gives its owner the many magical powers.