In addition to the use of four classical elements in the series, the fighting styles associated with each element are all taken from different styles of Chinese martial arts. The series employed Sifu Kisu of the Harmonious Fist Chinese Athletic Association as a martial arts consultant. Each fighting style was chosen to represent the element it projected. Tai Chi was used for "Waterbending" in the series, and it focuses on alignment, body structure, breath, and visualization. Hung Gar was used for "Earthbending" in the series, and was chosen for its firmly rooted stances and powerful strikes to present the solid nature of earth. Northern Shaolin, which uses strong arm and leg movements was used for "Firebending". And Ba Gua, which uses dynamic circular movements and quick directional changes, was used for "Airbending".<ref name="avatar2/index.jhtml"></ref> The only exception to these styles is Toph, who can be seen practicing a Chu Gar Southern Praying Mantis style.