The second major battle in the Music Room is to the north through the door that mirrors Malcolm's on the upper left side of the large central room. If you have an adequate Tracking skill, and use it just through those doors, you will find that battle much easier to survive. If you survive that battle, in the corner at the end of this room you can encounter Mannanan Mac Lir, the Celtic god of the sea. He is willing to assist you only if you can prove your mettle by solving his riddle. The riddle is solved in the Library.