Chi Kick

From LSWiki

    Perform Chi Kick

    General-Use Combat Maneuver
    Usage: perform chi kick [at <target>]
    Requirement to Use: have at least 600 points among 100% of martial arts skill, 100% of
        philosophy skill, 100% of pneumaturgy skill, 100% of evocation skill, 100% of
        bellerophrasty skill, 50% of discipline skill, and 50% of unarmed combat skill and be
        familiar with chi kick
    Typical Activity Cost: 22

    Focusing your chi into a weapon, you strike with your foot in a fashion that destroys the
target's spiritual body as well as the physical.

Learned by first meeting the requirement to use, and then asking to be taught by Musashi as an Aisenshi or by Rindol after completing his relevant task.