The Mask of Fire

Rowan dove backwards and flew behind a tree as the ground in front of him exploded outwards.
He'd been walking through the forest back to his cave hidden in the woods after a day of patrolling the city. Normally he'd simply fly home, but it was a glorious night, the moon was just rising in the evening sky as the sun set below it. He'd been landing atop a tree log when suddenly the earth had been torn open.
An explosion in the clearing ahead blasted the surrounding trees outward and left a 6 foot wide crater in the middle of the destruction. As Rowan approached cautiously he saw a glinting piece object wavering in the pit as the heat around it caused the air to shimmer. Rowan approached and felt the heat on his body.
Concentrating, Rowan prepared a small purple flame in his right hand and slipped down into the center of the pit.
As he approached, the heat radiating off the ground slipped around Rowan, his affinity for flame magic naturally giving him immunity to dangerous heat sources.
In the center of the pit laid a mask, embezzled with rubies and glinting in the light of Rowan's flame. cautiously stretching his hand toward it Rowan felt the heat radiating off the object, in fact, as he reached towards it it steadily got cooler. Rowan cautiously stepped back and he felt the mask flare up again, almost angrily. As Rowan stepped down further he touched the mask.
Instantly it flared up, amber flames enveloping it in a flurry of energy. Rowan shouted and shot a stream of purple fire onto it.
As the flames dissipated Rowan saw that the mask had remained unscathed, the aura surrounding the mask turned from the indigo coloring of Rowan's attack back to the amber glow from before and then faded away.
Reaching down, Rowan picked up the mask and, hesitating, placed it on his head cautiously. His eyes flared Amber and glowed through the mask's eyeholes. There were no whites anymore, and Rowan felt his demonic side stir as the mask integrated itself with him, his teeth sharpened and he let out a small cackle before coming to and pulling the mask away. Instantly the glow faded and his teeth diminished.
This requires... some looking into He thought, trying to calm himself and suppress his inner demon.
Holding the mask in his hand, Rowan launched himself into the air and back towards his cave.
1000 years of documented history at his fingertips, he'd see what he could come up with on the strange mask...