Helm of Unsurvivable Knowledge

As an action, a creature wearing the helm may open its mind to the knowledge inside. The creature makes a DC 15 Intelligence saving throw. On a success, it may ask the DM one question about cosmology, planar truth, divine structure, ancient history, or the true nature of a creature, location, or object; the DM answers truthfully but cryptically. The creature also gains advantage on its next Intelligence check made within 1 hour. On a failure, the creature takes 6d8 psychic damage and is stunned until the end of its next turn. On a failure by 10 or more, the creature instead drops to 0 hit points and gains one level of exhaustion. Once a creature uses the helm, it cannot use it again until 7 days have passed.