The Skirmish in Balin's Tomb, also known as the Battle of the Chamber of Mazarbul, was a battle between the Fellowship of the Ring and the goblins of Moria. The goblins had discovered the presence of the Fellowship, and while Gandalf was reading the harrowing tale of the fall of Balin and his Dwarves from the Book of Mazarbul, the goblins mobilized.