Book of shadows: Wither Limb

The caster chooses to wither either a arm or a leg of a humanoid. 

Arm: The target looses the use of one arm, which might affect what weapons and shields it can use. The creature must immediately drop all objects held in the withered limb, though it can shift a two-handed weapon it is holding in both hands to a remaining arm as an immediate action. Worn objects— gauntlets, rings, and magic items in the wrist slot—remain. This prevents the creature from using two-weapon fighting, claw attacks from that arm, and so on. If multiple castings of this spell wither all of a creature’s arms, it can’t manipulate objects or cast spells requiring somatic components.

Leg: The creature’s movement speeds are halved, except for flying or other speeds that don’t involve its legs. If multiple castings of this spell wither all of a creature’s legs, it can only crawl at a speed of 5 feet each round.

Wing: The creature loses access to any fly speed that depends on its wings if even a single wing is withered.

A withered limb can he restored by a successful dispel magic cast by a spellcaster of a level higher than the level of the with er limb caster.