Mage bane

Mage Bane- is a plant that when consumed causes a magic user to lose there ability to cast spells the roots of the plant can be powdered and added to other items such as potions or food with the only trace being a slightly bitter after taste depending on the individual plant and the skill of the person preparing it it can cause loss of power anywhere from a few minuets to days Mage bane itself is not magical and so is extremely hard to detect.