Universal AC Compatability... Moving Toward a Rosetta Clone

Paul, over at his blog, The Blog of Holding, talks about establishing a community standard for use when we discuss AC. Whether you favor descending or ascending armor class in your games there has to be a simple, easy to transfer from method to method, manner to notate and discuss AC; whether you favor descending or ascending AC.

There is, and it seems that all Paul had to do was consider how we think about and notate bonuses and penalties in D&D... a bonus is always a "plus" and a penalty is always a "minus" whether you prefer descending or ascending armor class.

Do you remember the first time you picked up and played Moldvay (or Holmes, or AD&D, etc.)? A naked humanoid had an AC of 10 and when he put on a suit of chainmail his AC improved by 5 to become a 5... huh? An armor class modification of plus 5 translates to AC's the actual numerical value decreasing by 5. So a suit of chainmail +2 improves a character's armor class by 7. Improving his AC to either a 3 (descending AC) or a 17 (ascending AC). So a simple method we can use to record AC values, making them accessible to all dungeon masters and players, is by just annotating the vale as the AC modifier.  Thus a suit of chainmail has an AC value, or modifier,  of +5.

Without even thinking about it I have been doing this for quite a while. Take a look at the AC values of the first few pieces of equipment on this list.