Wizards HATE Her! How to Play D&D for Free, Part 3: Inventory & Encumbrance
Last time, on wizards hating me... (link)
I expect this to be a somewhat shorter entry in this series. After all, inventory and encumbrance (whichever aspect you focus on) are ultimately an extension of the player’s game interface. This is literal within the fiction of the game, in that we often consider tools to be extensions of ourselves, and likewise whatever our characters carry is an extension of their capabilities in the game-world. It is also strictly formal, since inventory management is simply yet another mode by which players interact with the game-world through their characters. The difference between inventory management and character scores (whether abilities, skills, etc.) is that the former tends to be dynamic since it depends entirely on what the character is carrying at any time. It also tends to relate more to the various loops and situations of the game.
For example, inventory management for the dungeon crawl relates directly to the characters’ movement speed as well as their carrying capacity for weapons and treasure (and, in later rulesets, other items). Encumbrance is precisely the tradeoff between moving more quickly, being more capable in combat, or accumulating more treasure (or, later, having more resources on hand). It is thus the intersection between all these subsystems, and by extension it is the crux of the game in all its dimensions. I have previously written about these relationships in greater detail  . To summarize, inventory management, serves mostly as a restraint on player activity in order to proffer interesting decision making. Inventory management cannot be interesting if it does not impose meaningful decisions.
That being said, inventory management makes much more sense for certain games (read: problem-solving situations) than for others. There is a reason that encumbrance is often at the forefront of so-called old school play while it is often elided from games of D&D Fifth Edition altogether. In the former, as described, it is (in theory) the very crux of the game itself and it engages with all the game’s avenues for risk and reward. In the latter, it arbitrarily limits player activity without offering interesting decisions. Why not have a magical bag of holding or, even better, not give a shit? Anything more stringent serves to distract from the main point of the game rather than to proffer interesting decisions which are central to the game.
Inventory & Encumbrance
When it comes to implementing an inventory system, if doing so is desirable, it helps to implement one that isn't a pain in the ass. The original Dungeons & Dragons used a "coin encumbrance" system where all weights are measured relative to the weight of a single coin, itself one tenth a pound. This has the benefit of extra granularity since what you're really doing is adding a single decimal point to each pound measurement. It also interfaces directly with gold coins as the main kind of treasure; you can count up how many gold pieces you're carrying, and convert directly those to experience points. Since you're only measuring armaments and treasure, coin encumbrance facilitates these things without issue.
However, that's a very war-gamey solution. No one (well, most people) likes counting pennies, literal or otherwise. As resource management became increasingly important for the so-called old-school play style, new methods to keep track of player inventory emerged. One solution published in Lamentations of the Flame Princess is not to measure weights on the fly but, instead, to have the referee ask players to audit their own inventories when the situation calls for it. Players would just keep lists of items and count up how many things they carried; the more items, the more points of encumbrance their character has; the more points of encumbrance they have, the more slowly they will move.
The solution found in Lamentations is a precursor to the more contemporary "slot encumbrance", which was popularized by Knave where characters can hold a number of unit-items equal to their Strength 'defense' ranging mostly from 11-16. Some small items can be 'stacked' so that many fit inside one unit container, which is called a slot (bringing to mind computer games like Diablo). Large items might take up multiple slots, with common wisdom being that an item that takes two hands to hold takes the space of two regular items. This abstraction proves very useful for procedural classic-inspired play which focuses on resource management, since 'big' unit-items (of which you'll have around 10 in total) are much easier to track than long lists of things.
At a first glance, one might think that the main difference between the audit method from Lamentations and the slot method from Knave is that one relies upon a checklist ("Gain 1 encumbrance if your character is carrying more than 10 items") whereas the other relies upon the abstraction of items into unit-weights or slots. However, the more striking difference is that Knave does not have an encumbrance system but merely an inventory management system. It gives characters a maximum carrying capacity, but the total limit is the final word; there is no trade-off between carrying more or less items versus moving slowly or quickly. Goblin Punch published a post prior to Knave's publication that actually reconciles slot inventory with scaling encumbrance . Errant seems to have taken cues from all these, but it introduces additional complexity by attaching both maximum carrying capacity and maximum speed to characters' random ability scores . With so much variation in published works and with so much system-specific complexity in individual takes, it’s difficult to find a solution that feels natural and simple.
In Practice, What I'd Do Differently
My friends felt like they didn't have enough space to carry items according to Knave (characters already start with a lot of items, which is an issue I find recurrent in rulebooks that have stringent encumbrance systems). If I were more creative and knowledgeable, I would've probably followed Goblin Punch's cue in saying that they could carry more items at the expense of becoming slower and more tired; however, I'd feel bad imposing any made-up consequences for a condition which exists only in the fiction and not on paper, unless we had decided on that ahead of time. It's a central part of rulings over rules, sure, but you can't really ask that of a referee trying to be conscious of what is or isn't fair? Instead, we decided that they could all buy backpacks for some extra inventory space.
For games I run in the future, I'm not sure what I'll do. I'd like to accommodate my partner (and others, including myself!) who find many inventory management rules tedious at best. Besides, it's not like dungeon crawls always appeal to me aesthetically or even 'philosophically', so I wouldn't feel bad relegating inventory management to specific situations where encumbrance should actually matter. The difficult part, though, is that encumbrance works best when it meaningfully interfaces with the main activities of the game at hand. That is the whole point of it.
I think the simplest solution is to have a binary state of encumbrance and non-encumbrance. Tentatively, let's consider the original D&D armor class scale from 9 to 2 (descending). Let's add 1, so that our base armor class is 10. Then, let's say characters can carry up to a number of items equal to their armor class without being encumbered (see Luke Gearing's inventory rules for OD&D ), or else they can carry up to twice that number while they are already encumbered. This means that if you're not wearing any armor, you can carry 1-10 items without being encumbered or 11-20 items while encumbered. If you're wearing plate armor and a shield, however, you can only carry 1-3 items without being encumbered or 4-6 items while encumbered; this is only desirable if you are not expecting to carry anything heavy around. Good enough, isn't it?
That implies an armor class system, though, and that's its own baggage you have to lug around. The easier solution, anyway, is to just have 1-10 items be carried without encumbrance and 11-20 without (irrespective of armor worn). Next time, though, I will discuss the typical rules for combat in Dungeons & Dragons with a view to why they are how they are, and what symbolic underpinnings they have. Maybe a simpler solution for all this will emerge out of hindsight.