Mobeta's Mask, which is a thing from way back. Yes, it is a play to Majora's Mask.
On the left is the Object's original state: A pristine prison for the maniacal demon housed within, freshly crafted from, like... Clay, or wood, or magic silk, or whatever.
On the right is the object's "Current" state: A badly beaten salvaged relic from a crumbling temple or a sunken ship.