At the main menu, highlight the "Extras" option, then press Left(11), Right(7), X to unlock all levels in Single Mission Replay mode. If you entered the code correctly, you will hear a sound.
Hold Black + B or Black + A to perform your God-given magic. The magic works within the time limit. Different weapons perform different magics. Hold Black + White + B or Black + White + A to perform power arrows.
When Beowulf comes towards you and tries to attack, press White + Y to dodge his attacks. Then, quickly hit him with your weapon. Press White + Y again to roll and dodge his attack. Keep doing this until he has been defeated. He will also throw fireballs at you, but you can dodge them by rolling. Make sure you do not run into the ring of fire. If you get caught on fire, roll and the fire will go out. Also, watch out for his barbarians. They will sometimes come in and attack you. There are only a few and they are not difficult to defeat. There is also a health shrine and a power-up shrine where you are at, if needed.