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Quakedancing (Ex): As a full-round action, a quakedancer can shift its weight back and forth, gradually building up subsonic waves in the ground. After one full round, any creature within range must make a Fortitude save or be stunned for 2d4 rounds. (Radius and save DC vary depending on the quakedancer's age, as given in the table below.) Creatures with more HD than the quakedancer are immune to this effect, and flying creatures within range receive a +4 circumstance bonus on their Fortitude save. Unaffected creatures within range must continue to save as long as the quakedancer continues dancing. Once a quakedancer has completed its quakedancing, it can’t use this abilikty again until 1d4+1 rounds later. This is a sonic effect. The save DC is Strength-based.