The Cloaked Chest is a rare chest in Risk of Rain 2.
This chest may randomly spawn on the map, and yields a single item of random rarity. Since the chest is cloaked, being transparent with barely a hue, they can be very difficult to find. Using a Radar Scanner makes finding them much easier. They are also locked during the Teleporter battle, during which the red tendrils may reveal them.
They can be pinged to other players.