No one knows where Watcher found this artifact, what is known is that the device is incredibly powerful and seems to be custom designed for a being like himself or perhaps a dragon. Whenever he is seen, Watcher has the mantel and unfortunately efforts to find more information about it by others are always foiled by Watchers quirk of only answering with questions.
Where ever it came from the mantel seems to bend fate just a little bit making it so things just go a little bit in his favor no matter the situation. This protection has worked out well for him on more than one occasion, leaving him untouched when assaulted by swarms.
Game Mechanics