After the creature is released, run around the dome while turning the switches on by pressing Y. After pressing all the switches, four balls with come down from the ceiling. Get onto the magnetic gun in the middle of the room and make the balls come to you by using the magnetic gun. This might take some time because the monster will keep knocking you of the gun. When you have all the balls pointing towards you, a chamber will open above your head and the sword fragment will appear. Get off the gun, point up towards the sword fragment, and grapple it. When you have it, an intermission sequence will begin and the level will end.