Somewhere in the Dragon Magazine issues I've been perusing lately, Moldvay comments that the part of the Basic set he is most proud of is B60 "Dungeon Mastering as a Fine Art", where he gets to impart his own experiences as a DM to newbie DMs. I leave the entire passage transcribed here below without further comment: The success of an adventure depends on the DM and his or her  creation, the dungeon. The DM should have the dungeon carefully  mapped out before play begins. Even so, a DM will quickly find  that it is impossible to predict every possibility. After all, there are  several players, and only one DM! It is not unusual for players to  find a solution, or pose a new problem, that the DM has not even  thought of. It is very important for the DM to be flexible. It is important that the DM be  fair , judging everything without  favoring one side or another. The DM is there to see that the ad venture is interesting and that everyone enjoy...

Smaller numbers are better. It's not always  true in RPGs, but it is generally true. It's easier to work with in terms of calculation, but perhaps more importantly it makes it easier to intuitively gauge the significance of the numbers. You can feel the impact of a +1 on 1d6 more than you can on a d20. The older I get, the more I appreciate smaller numbers. The art quality in OD&D may be lacking, but the art direction  was pretty dang good. Number creep started with Greyhawk, continued in AD&D, really took off with 3e, before being scaled back a bit in 5e, with its notion of "bounded accuracy". 5e's notion of bounded accuracy still yielded a greater inflation of numbers than Classic D&D (Holmes, B/X, BECMI, Cyclopedia) which held back a bit on that front but still had slightly higher numbers than pre-Greyhawk D&D. One of the most obvious parts where number inflation took off is hit points. And in this regard, I quite appreciate the HD scale in OD...

 I know, I know. Addition is easier than substraction, what kind of backwards grognard do you have to be to like descending AC in 2024? I get all that. But hear me out for a moment. My argument is that whilst ascending AC may be marginally easier to calculate to begin with, descending AC offers something different - A more intuitive appreciation of what the numbers mean  and how they are bounded. AD&D Armors We'll start at the very beginning. Before that, even. An early draft for the first version of D&D: Target20  was basically the original conception. Deduct AC from 20 and you have your attack target roll. Which is of course also how one converts descending AC to ascending. One wonders why they didn't just include this explanation to begin with, alongside a +to hit modifier, instead if messing with THAC0. The math in the draft is a bit off, but it suggests another, even more intuitive, layer. If we stipulate that one must exceed the AC and not just meet it, it m...

There are three armor types in classic D&D (B/X, BECMI, Cyclopedia). Leather (AC7), Chain (AC5), Plate (AC3).  In terms of classes, fighters, elves, dwarves, halflings and clerics can use all armor, thieves only leather armor and magic-users no armor. This is important, because this frames why people wear the armor they do. Why would anyone wear leather armor? Because they can. That means thieves. Thieves can wear leather, magic-users can not and that gives thieves an advantage. It's also cheap and only weights half what chain weighs. There are no real downsides to wearing light armor over no armor, except weight. There is rarely much reason to wear chain armor though. Plate mail is only slightly heavier and pricier and any class able to wear chain can also wear plate. In other words, chain is almost never a meaningful choice. It's going to be all Clyde Caldwell for this entry. It's All AC5, baby. So maybe we should find some reasons to make the choice between chain and...