I've searched the board and can only find stuff on HOW to kill him (I know that already - hit the bugger hard ), and there was a mention of the silver dragon opening the locked drow door to the NW of the dungeon. I haven't come across this dragon, and I didn't wanna read up too much on him 'cos I don't like spoilers.
I've looked everywhere down there, returned to the surface and been told that I should go back when the quest is finished. Doh!
Have I missed something out (I haven't been down to the MInd Flayer dungeon yet, but I shouldn't think I need to do that first).
Can you help me out? My walls are getting full of head-shaped dents.