The Medusa Mask is the source of power for Roger Hayden; the Psycho-Pirate. Hayden first learned of it's existence from the first Psycho-Pirate, Charles Halstead, while sharing a cell with him. Originally, several Medusa Masks existed, each dominating a single emotion, but Hayden re-forged their metal into a single faceplate. While this gave him power above all the emotional spectrum, the mask forced a form of emotional vampirism as its cost upon Hayden, forcing him to consume emotions to survive. The Medusa Mask allows the Psycho-Pirate to promote and project emotions in other people, and during the "Second Crisis" in Animal Man, the mask holds the remnants of the multiverse, with the capability to summon any of the destroyed characters of the countless realities that once existed. Hayden appeared to be consumed by its power and it was left to be worn by former physicist, James Highwater. Hayden would later return as the Psycho-Pirate, with the Medusa Mask in tow. When Hayden upgraded his powers with Neron's influence, the mask's metal would replace half his brain and would manifest as a golden eye patch, though by the time of Hayden's stay in the Slab, it had gone back to its familiar shape. In this capability, Alex Luthor used Psycho-Pirate in his quest to recreate the multiverse until Black Adam killed him by shoving the mask through his head. The mask appeared in the Raven limited series, and though the titular heroine destroyed it, its power lingered, and started affecting scientists researching its schematics.
Much later, during the Blackest Night, Conner Kent stole the mask from Black Lantern Roger Hayden, and using it on him, discovered the mask's powers were enough to cut the connection between the Black Lantern Ring and the corpse it was controlling, allowing him to destroy Hayden and Black Lantern Kal-L. Shortly after, a fleeing ring shattered the mask once again.
Power and Abilities
Powers and Abilities in the New 52
The Medusa Mask gives the wielder over every mind on the planet and the power to twist all the thoughts, memories, all secrets inside them. It has also been able to get past the mental shields given to Superman by Orion. It also protects the bearer from other psychics while amplifying his own power. The mask allows the wielder to drain people of their psionic energy.