The quest Wrath of the Lich King in the Halls of Reflection does not work. We get all the way to the end (yes, staying toe to toe with Sylvanas), the Lich King catches up and starts channeling Harvest Soul on Sylvanas, and the gunship rises in the background. The gunship should shoot at the Lich King and interrupt the channel. But that never happens. The Lich King just keep channeling. The dungeon cannot be completed and the player must hearth out.
EDIT: This issue is covered in another thread (Halls of Reflection - cant finish). This thread can be closed.