Instructions
Make your way to "Faraway Avalon" and begin the second boss fight with King Arthur. Watch his sword, as it will attack you either in a side-to-side motion or by stabbing right at you. Avoid the slashing motion with his sword by running in between the slashes to avoid them and avoid the stabbing motion by swerving out of the way.
Run back and forth to avoid the pink beams King Arthur shoots at you. Avoid his "Charge Attack" by running to either side as he charges. Keep your "Soul Gauge" as full as possible and slash the red items he throws at you to hurl back at him.
Move close to King Arthur while you have enough "Soul Surge." Jump and hold "B" to attack him with your sword. Follow the blue Wii remote commands as they appear on the screen to duel with him several times. Go for the kill by slashing repeatedly after wearing him down in the duel.