Gnoblar Bestiary unlock.
1. Go to Badlands at 40k, 37k and kill Bloodmaw Gnoblars until you get a Bloodmaw Gnoblar's Nose. (1 BoP item)
3. Go to Black Crag at 40k, 11k and kill Burnmaw Gnoblars until you get Burnmaw Gnoblar's Shiny Bits. (1 BoP item)
Make sure you have only ONE of each item then right click one of them. It will turn in to a Limited Edition Gnoblar Collectables! bag. Once you have this, you can go to the library and buy the Oathstone of Karak Eight Peaks, which is one of a set of two jewelry pieces.