Verfluchte Zwillingsschwester

The Verfluchte Zwillingsschwester (Germ. Verfluchte "cursed" or "hexed" + Zwillingsschwester "twin sister") is a spell used by Hexenbiest's to take away a Grimm's powers. Once the potion is complete, the Hexenbiest responsible places a Witch's hat over the top of the cauldron containing the potion and inhales the vapors of the potion through the top of the hat allowing the Hexenbiest to turn into another person that they have gathered the DNA (ex: hair) from, usually the sexual partner of the Grimm. Then to take the powers from the Grimm, the Hexenbiest in their newly disguised form must have sex with the Grimm.

Side Effects
Within a couple days of the spell being completed, the Grimm and the Hexenbiest will both randomly get strong headaches at the same time which allows them to see through the eyes of the other for a brief amount of time.