The Archive’s infinite Hall of Packs contains samples of every universe’s carrying aids. Despite several attempts at the task, you have been unable to devise a definition for a bag. Perhaps it is related to the handles and straps for holding them, but that includes trays with handles and trousers with suspenders. A “closeable container” would includes boxes and buildings. Portability as a key feature still allows vehicles, and anything in outer space. Even all requirements together — a portable, closable container designed for ease of carrying — leads to the uncomfortable classification of most living creatures as bags. Perhaps this problem is is unsolvable.
Last time we looked at encumbrance and gear, and the need for a multi-faceted solution. Today, we are assembling the encumbrance mechanics. This is a frame for supporting other subsystems. It will look a little odd at first, but should begin to make more sense once we eventually add the subsystems.
The Scaffolding
Building a framework from scratch is tricky. Fortunately, we do not have to. D&D already has a good high level framework system that we can learn from: actions in combat.
Action Economy
Every monster and class works differently, and has different abilities: one attack, multiple attacks, spells, flight, communication, using potions, or any other interaction the players come up with. If every possible action the PCs or monsters could take had to be defined individually, along with the way all these actions interacted, the rulebooks would be several volumes long, and we would read them even less than we currently do. Instead, 5e defines actions in combat, and lets everything else attach onto this.
Most of the time, PCs and monsters will want to “do a thing” — a spell, attack, or other signature ability. That is easy to manage: give them an Action every turn. Repositioning is another activity that is so common we always want to offer it, so we get the Movement. Many class features are not worth a whole Action, but also must be rationed to simplify maintaining balance — Bonus Actions cover this. Finally, to keep players engaged when it is not their turn, add Reactions.
Crying is a free action.
And then we break the rules by adding Legendary Actions.
To summarise the architecture of the system: the action economy defines a series of different hooks on which we can hang different abilities defined elsewhere in the game. There are also some mechanically insignificant activities that can use the “free” action hook. Some effects, like Haste, can change the action economy. And sometimes, DMs can break the rules.
Backpack Economy
This is unexpectedly similar to the inventory problem: some things are not important enough to worry about in detail, like ink for a quill; some are regular things we expect adventurers to use, like armour and weapons; non-material assets and wealth will feature in this differently; and sometimes we need to make exceptions for when PCs (try to) carry unexpected objects, like building-sized dragon skulls.
Here are the hooks of the Backpack Economy. In future articles, we can flesh out the systems that will attach onto them — for now, a high level idea is all we need.
The Pouch
The Pouch is the “free action” of encumbrance. Anything that PCs should just have access to goes here, as well as miscellaneous items they pick up that do not doing anything important. Items in the Pouch should not give a mechanical bonus, in the same way that talking strategy as a free action has no mechanical effect. It is purely for flavour and inspiration — this will include Kit, and other evocative items that can inspire players to try things that might otherwise not come to mind.
The Pack
Most items will be carried in the Pack. This will include the PC’s worn and wielded gear, and anything in their backpack or that they carry while adventuring. Unlike the Pouch, the Pack is finite: there are a limited number of slots that the player can use.
How many slots should the Pack have? This is tricky to answer without the rest of the systems, so may need changed later. At the very least, each PC should be able to have: armour; a weapon, spell focus, or item for each hand; a healing potion; rations; a tool of some kind; and three attuned magic items. That gives us a minimum of eight. The upper limit is harder to reason about without understanding how much gear we expect PCs to accumulate. Ten may be reasonable at first: most PCs will not start play with three attuned items, so this gives them five spare slots. At higher levels, they could gain additional Pack slots through hirelings or mounts. At lower levels, they should have the flexibility to do what they want, but the limit should be close enough that they do have to consider their choice of gear.
Unlike other encumbrance systems, this is not tied to strength. Doing so would introduce a huge amount of swing — even if we just added or removed slots based on the modifier, we could end up with PCs with twice as many slots as others. Either the restrictions will be too tight on one, or not tight enough the other. That does not mean we cannot do this — only that we must take care. A more reasonable adjustment may be to use racial abilities: the goliath’s Powerful Build could give them an extra two slots, for example.
Lifestyle
PCs can accumulate some amount of wealth in non-material things — or at least less-material. Perhaps they hire followers or armies, or have a home or castle. We will also need an abstraction over general wealth to help with bribes. Finally, we need ways to add “items” that add pack slots, like masterwork backpacks and pack animals.
Lifestyle covers resources the PCs have that do not have a carrying constraint, but which do have a mechanical impact (unlike the Pouch). This communicates to the PCs how they can use things. For example, a “Pouch-Class Hireling” creates narrative options — they could watch a prisoner, or deliver a message — but provides no mechanical bonus, while a “Lifestyle-Class Hireling” would give a bonus. The first could carry a torch and light the way; the second could carry a torch, giving you a bonus on perception checks. The exact mechanics can be defined in whatever subsystem we attach on to this.
Special
A plot artifact that must be contained in a special box to stop it corrupting the party? A dangerous prisoner? A ship being dragged over land? These items are Special. They cannot be carried without special considerations, however there is no limit beyond that. The party can carry as many special items as they want, so long as they meet the requirements for each.
These items, by their nature, must be defined by the DM on a case by case basis, and are generally plot-related rather than giving mechanical bonuses, like a battering ram that lets you break down a gate, rather than one that gives you a bonus on checks you could otherwise attempt.
Deprived of Gear
Just as Legendary Monsters break the action economy, some situations will break the encumbrance system. If the PCs are somehow deprived of their gear, they cannot use their gear. We do not need to do something more complex: as always, DMs can determine what is reasonable.
Final Architecture
Our four types of gear are: things without an encumbrance cost giving mechanical bonus; things without an encumbrance cost giving no mechanical bonus; things with an encumbrance value giving a mechanical bonus; and things with an encumbrance constraint giving no mechanical bonus. As we flesh out subsytems, we can work out which category they fall into, and enforce the rules as appropriate.