You don't know what it is? Well I can't just tell you... that would make him really mad. He's not just a prince anymore... he's the king!
Meet me at the Court of Bones, north of Icecrown Citadel and you can see for yourself.
There you are. I started to wonder whether you'd show up.
NotesMatthias Lehner can be found on the path between Corp'rethar and Icecrown Citadel at [49.2, 73.1]. You should be able to see him from the Argent Crusade encampment there.