A white porcelain mask with a aura of shadow hanging about it
A white porcelain mask which always seems to have a thick shadow hanging underneath it, regardless of the light it is in.
The mask has the ability to make itself invisible.
It also allows the user to ‘wrap shadow’ around themselves, whatever that means.
Finally, it allows the user to transform themselves into a living shadow. No idea if that was is reversible or not…
The magic item seems to be bonded to Byron, and also seems to have no downside. Whether it is simply not known, or whether (as Varus suspects) it is because it is a living shadow given form remains to be seen.