At the Fractured Plain Sourcewell, pick up the Empowered Relic, then kill 5 Goblin Diggers and bury 4 Farclan Remains. When that is done, destroy the Goblin Idol to find a note detailing a meeting between Karris and the goblins to happen very soon. Go to a short arch over a pyrocaust nearby and click on the rock there to hide so you can witness the meeting.
It becomes clear that Karris has ordered the diggers to unearth the dwarf remains to use them in some ritual to take revenge on the Farclan for using his Pyrkari to power their Malgems.