Speak to General Narvion, in the tree gnome stronghold, he will tell you that the king has been missing for week's and would like you to investigate. Go to his throne room (first floor) and search his throne, you will find some lines under it, and engraved words. Tell Narvion this and he will come with you to check it out. Go back and search the throne again. Now you can see there's a trapdoor and now go down there. Narvion will be there fighting a level 390 Warbeast on his own and you see him kill it. The spell will now where off and you will be in his lair.