Otto's Tones of Forgetfulness

When the wizard casts this spell, the ears of the target being are filled with exotic tones no one else can hear. A being who fails to make a successful saving throw vs. spell loses all memory of one non-weapon proficiency. The wizard can choose the proficiency if he knows the being to possess it, otherwise a non-weapon proficiency is randomly chosen by the DM. Any attempt to use the proficiency meets with failure. A being whose saving throw is successful still suffers a -2 penalty to the chance of success with the proficiency for the duration of the spell.

The material components are a string from a sitar and a wooden mallet.

Notes: Uncommon or rare spell (WoG).