Perdo
One of the fifteen Hermetic Arts, Perdo is a Technique used in Hermetic Magic intended to destroy or degrade its target.
Perdo cannot improve something, moving it closer to its ideal form - thus, Perdo can be used to serrate a sword, but not to sharpen it.
Changes caused by predition often persist naturally, as the destroyed qualities usually don't resume by themselves. For example, a pit dug by magic will not naturally fill so remains empty. In contrast, a person turned weightless by Perdo-ing his weight quality will regain his weight once the magic ends.
References
- ArM5 ??.