We have been seeing some Skull weapons in the treasure chests. I didn't think much of it when all of them I was seeing had a magic item rating (Lesser, etc.) and mods on them, BUT........then I got two Skull Longswords that have no magic item rating nor mods. It is a simple "Exceptional" weapon that a Smithy would make (minus the DI that my Smith would have put on it making it). We don't get any other weapons without mods, etc. out of chests, so I think these "plain" weapons are going to come into play in this story arc. I suggest you keep the plain ones you find.