Charms designed to inflict harm, often called “Battle Magicks,” may deliver up to (POT) points of damage. This way the damage may be varied at the caster’s discretion on a point-by-point basis, as desired.
Most dweomers inflict damage that can be reduced by the target’s armor, due to a more physically insubstantial or superficial form of attack like frost or fire or an enhanced or even supernatural sharpness in cutting or piercing that directly diminishes AR, where some inflict impact damage that is readily reduced by armor, less focused on destroying the target’s armor and more definitely felt through it.
Magickal damage that can be defined as primarily impact or concussive is most likely to regularly bring the combat rules for Knock-Back into play if it is sufficient in magnitude.
The manner in which charm inflicts wounds and interacts with any armor worn is dictated by the force generated that is actually causing the damage and the way in which it is applied, whether it be frostbite, fire, electrical, acid, poison, cutting, bludgeoning, piercing, etc., according to its description.