Arbiter's Disc

Deep in the Feywild, on top of an invisible mountain, a small temple to a forgotten god sits. Were they able to view it clearly, being on an invisible mountain and so on, an architect or scholar might question whether it was built as a temple at all. Whatever it's origins, the Arbiter's Sanctum exists and serves a single purpose - to guard and determine those appropriate to wield the Arbiter's Disc.
The Disc is a device for those who have a clear judgement in their heads - that someone must die. The Sanctum will test this conviction - assessing the visitors' understanding of the character and actions of those they have targeted, and also showing a possible future without this individual to give them pause to consider the impact of their decision.
Once these tests are passed, the Disc is quite amicably passed on by the Arbiter - a powerful spirit of few words. With just this knowledge, the Disc might appear to be a tool of assassins, but this is not quite the case.
The Disc can only be used by multiple people, all sharing the same conviction, each placing their hand on the rim of the artefact while in the presence of their target. The more people participating - adding their conviction - the easier it is to wield. A single individual, or even a pair, would have no hope of activating the devastating power of the device.
This was most recently used to annihilate Granny Longtooth during her conflict with Nowhere (for further details do see The Trial of Nowhere. It took 4 people, and then it was very difficult and almost didn't work at all, the energy emitting from it flickering and wavering as the convictions of those participating waned in the face of actually killing someone so utterly.
Once used, the Disc vanishes, returning to its mysterious sanctum, for another to come and claim its power. It is, in the right hands, in the right circumstances, the Ultimate Weapon. In the wrong hands, or uncertain hands, it is just a pretty round thing - like a bronze shield with hand holds around the edge.

Rarity

Unique, Legendary

Weight

10lbs

Dimensions

3 ft diameter