Answer
The Shaman King opening theme in 2001 performed by Megumi Hayashibara is called "Over Soul." It serves as the introductory song to the anime series, setting the tone and capturing the essence of the show's themes and atmosphere. With its energetic melody, powerful vocals, and catchy lyrics, "Over Soul" immediately immerses listeners into the world of Shaman King, captivating fans and leaving a lasting impression.