Chronicles of War
In the core rule book there is a section on ineffective items. In which they mention you can’t use a bludgeoning weapon to cut a rope. Which I’m going to expand. While making items get destroyed more, I’ll be using common sense as well. A robe has no hardness and only something like 1 or 2 points. This represents how easy it is to get through it, but an arrow through a robe leaves it far from destroyed, and even a sword slash doesn’t necessarily destroy it.
This will be arbitrated on a case by case basis. A giant with a large falchion who gets a critical hit against the mage and takes out half hit hit points with one slash will absolutely tear a large enough gash in the robe to have it count as destroyed, while the drow blade-master wielding a long sword won’t create enough damage to destroy the robe.
Armor Destruction Through Critical Hits
Armor is potentially destroyed through critical hits. It is imperative for soldiers to keep their armor in perfect condition. Every critical hit automatically deals the normal damage to the armor. Obviously you still subtract the hardness of the armor, but every critical hit against a character has the chance to deal damage directly to the armor as well.
Example: A critical hit by an Ogre deals (2d8 + 7) x2 damage. He rolls 8 so the attack deals a total of 30 ([8+7]x2). Which deals (15 [the normal damage]) directly to the armor. So if the armor was mithril or adamantine it would suffer no damage, however if it is iron or steel armor it will take 5 hit points worth of damage.
Note: This adds an extra layer of danger to the incredibly strong creatures such as giants. While even adult dragons are going to at most lightly damage metal armors with a single critical attack, a giant can completely destroy even a suit of full plate with two critical hits.