# Can Piercing result in negative Armor?

As per the Dungeon World SRD:

n Piercing: It goes right through armor. When you deal damage with n piercing, you subtract n from the enemy's armor for that attack.

So the idea is that a piercing attack will ignore armor to some extent. But what happens when the piercing exceeds the armor rating of whoever is taking the blow?

As far as I recall, there isn't anything that says whether or not armor can drop below zero. If I were to apply the piercing tag's "subtract n from ... armor" strictly, then that would essentially mean additional damage.

Of course, the other argument is that the leftover (n - armor) piercing does not add damage because the attack's normal damage is simply dealt as if unhindered (assuming that either armor cannot be negative, or that negative armor is not factored into damage calculations).

So the crux of my problem is: Is there a rule that specifies if Armor cannot be negative?

Also per the SRD,

n Armor: It protects you from harm and absorbs damage. When you take damage, subtract your armor from the total. If you have more than one item with n Armor, only the highest value counts.

If the attacker has more piercing than the defender has armor, then the attacker simply exceeded the ability of the armor to absorb damage. It doesn't actually do more damage.

Look at it another way. If piercing did do extra damage, it would be indistinguishable from a +damage modifier.

• As far as fiction goes (and I understand DW is about the fiction, not mechanics), then yes that does make sense. However, from a mathematical / mechanical perspective, without a ruling that prevents or discards negative armor, one can subtract -n armor from damage -- and subtracting a negative value is essentially addition. On the other hand, you're right about it being indistinguishable from +damage, if applied in the manner I described. Dec 7, 2016 at 4:29
• @LiveMynd Dungeon World explicitly doesn't prioritise counter-intuitive perspectives. The fiction is explicitly, RAW, the correct perspective when figuring out how things work. So no, no negative armour. Dec 7, 2016 at 7:13
• Noted. I just had to get some clarification, as a couple of my players come from a DnD 3.5 background and I have to learn how to keep them in the fiction, and not in the tactics. Dec 7, 2016 at 7:18
• If they need a realism argument, consider the fact that many armor-defeating technologies rely on applying overwhelming force to a very small area - they punch small holes in very hard materials. Apply that same level of force to a softer target, and it goes right through. In the case of bullets and blades, it actually leaves a smaller wound channel. Nov 26, 2018 at 19:31

The real question is whether negative armor makes any fictional sense, the answer to which is “not really”.

Perhaps a terminology change would correct the ambiguity:

"When you deal damage with n piercing, you negate n levels of the enemy's armor for that attack."

I'm not sure if it's obvious to all, but the idea is that you can only negate what's there; you can't negate something below zero.