The game won't allow me to extract a weapons essence from \aITEM 1290502845 -564701944 0 0 0:[Belliza's Greatshield of Honor]\/a It's a FABLED Secondary slot item, with the tags ATTUNEABLE, HEIRLOOM, INFUSABLE -- so you SHOULD be able to crush it for the weapons essence. To add insult to injury, when I tried to transmute it, it gave me an Infusion of the Planes, from two expacs prior.
