The old-school Dungeons & Dragons game of my youth was practically a survivalist game. It was deeply interested in how many torches, days’ rations, and such you were carrying. Today, not much thought is given to the bookkeeping aspects of the game–except among those who play in OSR (old-school Renaissance) D&D clones.

Even in those, I suspect, most of the consumable supply question is hand-waved away. No one really wants to do bookkeeping but a bookkeeper. (Gary Gygax was a bookkeeper.)

But there’s an easy way to account for such materials: roll for it.

Mundane Consumables

Consumable materials can be lost, contaminated, or used up more quickly than expected in the course of combat, falls, camping, and other adventuring. Near the end of each adventure, the game master should roll 1d20 for the heroes’ consumable supplies. Check difficulty class 3 for food, torches/lantern oil, each character who uses arrows or material components, etc. On a 1 or 2, that consumable is down to 1 or 2 “uses” left.

In the case of arrows and crossbow bolts, you are down to 3. So, in any later combat, you only have three shots (you can retrieve them for reuse later, unless you hit a creature that runs away with it). This can happen even if you haven’t shot very many shots, since a tumble or attack can break some, and you might not even realize it until you start pulling out headless arrows.

Potions Stink (Eventually)

Another aspect of consumable supplies is potions. Players tend to hoard what they have until they “need”, but often go down fighting without having used all their supplies. To get them to drink and be merry, just say that potions have a short shelf life. This means that potions should not be found among dungeon treasure, at least not any that are still usable.

Potions should be purchased or made to order before the adventure. Use it on that adventure, or it spoils. This is a convenient way to get the heroes to spend some cash. The price might be, for example, double what you might get charged to get a spell cast on you.

Level of Spell Emulated	Price (gp)
1	40
2	80
3	160
4	320
5	640
6	1,280
7	2,560
8	5,120
9	10,240

You might even make potions able to replicate spells that don’t affect the imbiber–drink a potion, throw a fireball. Those might cost more.

For fun, you may occasionally throw in a potion that has gone bad but doesn’t yet stink (maybe if you roll a natural 1 on a d20). Drinking this results in the imbiber suffering a minor wild magic effect, same as if you drink a potion while another is still in effect.

This also works for other kinds of magic items that go bad after a certain time, such as magic fruit or berries. You can tell it’s ripe when you find it on the corpse of the wizard you killed, but it needs to be used before it rots, which means by the end of the adventure. But maybe magic nuts last all thru your next adventure.

Scrolls Can be Ruined

Magic scrolls are a great way to put powerful magic in the hands of the adventurers before they would normally get access to that spell–or in place of them ever learning “legendary” spell.

Unlike potions, they last and last–but they’re still subject to loss of they get wet or burned. If the wizard gets dunked in a pool by a trap door, he may suffer no damage, but ask what parchment products he’s carrying. If the player is smart, the character will probably have a “waterproof” scroll case, but you should roll to see if the seal has failed: difficulty 8 (with advantage for a fine quality case).

Convert Items to Candles

Certain kinds of magic items can be converted to being candles, which manifest their enchantment only when lit. Candles eventually burn down, of course, limiting their usefulness. Each candle lasts one hour–altho small ones might only last 10 minutes–but may be extinguished at anytime to save its use. They blow out as any normal candle.

Examples:

• Candle of Discovery: When lit in darkness, one of these candles will illuminate a 10-foot diameter area and reveal anything deliberately hidden, including secret doors and traps as well as invisible creatures and such.
• Candle of Silence: Lights as a normal candle but radiates silence in a 10′ radius. Lasts 10 minutes.
• Candle of Invisibility: Lights as a normal candle but gives the bearer invisibility as the spell (including being dispelled if the bearer attacks). The candle’s light is visible only to the bearer. Lasts 10 minutes.
• Candle of Magic Detection: When lit in darkness, this will illuminate a 10-foot diameter area and detect magic as the spell.
• Candle of Protection from Evil/Good: Lights as a normal candle but gives those within 10 feet protection from evil (or good) as the spell.
• Candle of Wild Magic: Lights as a normal candle, but creates a wild magic zone with a radius of 10 feet. And use of a magic ability or spell within 10 feet results in a minor wild magic effect.
• Candle of Protection from Magic: Lights as a normal candle but gives those within 10 feet protection from magic. They succeed on all saving throws versus magic spells and abilities, take half or no damage (if they save) for damaging magic that doesn’t normally allow a save, and halve the duration of spells that affect them for a certain duration.

Renewable Magic Items

Renewable magic items are ones that regenerate or refresh after a certain amount of time. Even if they don’t go bad, this means that if they don’t get used, their value was wasted, because it would have renewed anyway.

For example, a magic weapon that has a thrice-per-full-moon power. They can’t abuse it by overusing it (it’s basically three uses per adventure, unless you decide there’s a full moon in the middle of the adventure), but they might as well use it or the power is wasted.

Or a magic item that is mundane in function but which renews itself overnight, like a perpetual torch.

Items with Charges

Renewable magic items are better than items with a set number of charges, since it’s unlikely they would ever use all those charges anyway. Therefore, keep the number of charges quite low (2d6 at most) and give those a shelf life too. Perhaps the wand has 8 charges, but it loses one charge every full moon, whether it’s used or not.

Note that this means that there can be no such magic items found in an ancient ruin that would still be useful.

Circle of Enchantment Preservation

To get around that last note, you could put the item in a “circle of enchantment preservation” that stops the magic from draining away as long as the object remains within its (very small) area of effect. It’s a mid-level spell (and so not available to the heroes until they get to pretty high level, if ever) and uses a circle of gold wire; it lasts until the gold wire circle is moved or bent (so it can’t be carried away and used by the PCs).

This could preserve not only the charges in a wand and similar items but also keep a potion from spoiling.

Sword Spoilage

The extreme end of this idea is making virtually all magic items expire. The enchantment on a +1 sword might only last until you roll a natural 1 on an attack. Or, indeed, it could just break altogether, like any other weapon failing a check after a natural 1. And +2 armor might drop to +1 when it takes a critical hit. Only a legendary item might keep its enchantment for a thousand years.

This is less brutal if you allow the heroes to buy further enchantments. Pay 1000 gp to the right sorceress, and get a +1 added to a weapon or armor (+3 max). Or pay half the value of a magic weapon to get its effect added to yours. This would only work for items that are finely crafted, naturally, so it gives another incentive to heroes to buy fine weapons and armor.