The Overseer Music Box is a device used by Warfare Overseers, which, when used, prevents the use of any supernatural abilities within range, and can send out a sound-wave barrier to keep Corvo Attano away.
As such, Corvo is required to use his ranged and melee weaponry to combat them. The Music Box can also harm Corvo by firing Windblast-like waves, that keep him away, deal heavy damage and negate magical powers.
Corvo first discovers the device in the workshop near the office of the High Overseer, where it is described in a note called "Holger's device." According to the studies of the Abbey of the Everyman, the box produces "mathematically pure" notes, which act on the theory that there are hidden waves throughout the natural world.
In an audiograph recorded by the Abbey's High Artificer, the concern is raised over whether or not the mechanism and its effects are themselves magic. However, this issue is not addressed by any other members of the Abbey.
Overseers carrying this music box can be especially deadly, as they share an immunity to shots to the face with the more common Overseer, as well as using the box itself as a bulletproof shield. Their great range, ability to block damage, and Corvo's hampered ability to flee without his powers make them a priority when in combat.
A good strategy to kill them would be to fire an incendiary bolt at the Overseers legs, as they move slowly due to their music box and are easy targets. Grenades or explosive bullets will also do the job. If taking the low chaos approach, always make sure to get rid of Music Boxes first. Their music can stop Corvo mid-Blink, and can cancel Possession.
- Even though it is implied that Bone Charms, which usually emit some warmth, turn cold and useless close when in the vicinity of the music, Corvo's charms will continue to work normally.
- An Overseer Music Box can be found the mission High Overseer Campbell. It is located in The Backyard in a workshop. Next to it are two notes with information about the device, and if Corvo activates it, his supernatural abilities will be suppressed.
- Two City Watch Officers can be overheard discussing a rumor that a group of Overseers declared a woman a witch because she lost her voice just as Overseers passed by with a Music Box
Enemies in Dishonored