Complex sentence: Odin himself makes some impressive and doomful appearance, making the battle a Götterdämmerung... more Wagnerian in tone than the utter end of the world predicted for Ragnarök, though it is indeed the end of a world.
Split into simpler sentences: Odin himself makes an impressive and doomful appearance, making the battle a Götterdämmerung. This is more Wagnerian in tone than the utter end of the world predicted for Ragnarök, though it is indeed the end of a world.