Normal: The target changes their shape as you see fit.

You must The target must succeed a fortitude save or is transformed into an animal or magic beast as if using beast shape I at speaker level 1 and 1 higher every two speaker levels. In this shape the creature cannot use their ordinary racial abilities, abilities to speak, cannot use spells or spell-like abilities. However, the CR of the base creature is capped at half the caster level round up.

You may also use this effect to use alter self as the spell.

Reverse: You end all forms of change shape to make a creature return to its original form.

The target must succeed a will save or is transformed back into their original form.