Over Soul
To enter the Shaman Fight, Yoh must hit, at least once, the Shaman Fight priest Silva. The task is not easy, though, because Silva uses a different technique to fight with his guardian spirits.
Aired 26/09/2001EP 13 - Over Soul

2001
Shaman King
Shamans possess mysterious powers that allow them to commune with gods, spirits, and even the dead…and Manta Oyamada's about to learn all about them, because his class just welcomed a new transfer student: Yoh Asakura, a boy from way off in Izumo…and a shaman in training!
(Source: Kodansha USA)