Originally, in this post, I explained a small modification to the known AC system used in D&D up to advanced second edition. My goal was to reintroduce something that was lost when the game migrated from wargaming to RPG, but then, as a final afterthought, I made some calculations and discovered that, well, my changes made little (although not insignificant) difference. Preceding a post with a disclaimer like “what you are going to read may not be as useful as it seems” is probably not the best hook, but I still believe there are a few interesting bits here and I may also have unwillingly solved an ancient argument about AC vs. damage reduction that sometimes still rises from its grave (spoiler: there is surprisingly little difference in the long run unless you make a completely different system from scratch.) Besides, I’m a believer in the idea of publishing negative results, even if they are not as eye-catching as positive ones.
It’s a fundamental element in most RPGs: Strength modifies hit chance and damage. From time to time, a few heretics claim that the main attribute for close combat should be speed, dexterity, or something like that, but the answer to these people is always the same:
“You are as ignorant as you are [probably] ugly. For a trained warrior, speed is strength, and strength is speed. The damage any object may cause is basically speed x mass, so the bigger and stronger you are, the faster you will hit, and the more brutal you will be.”
The idea that, somehow, a nimble fighter would beat a 240lb man probably comes from the same crazy hole that gave us Waif-fu and similar nonsense.