Usage dice are a direct rip from the ORS hack The Black Hack. When an item described has Ud and then a number after its name, it is considered to be a consumable, limited item. The ‘Ud’ stands for Usage Die, the number indicating what size die it is. For example, oil (Ud6) has a Usage Die of 1d6. When that item is used its Usage Die should be rolled. If the result is 1-2 then the Usage Die is downgraded to the next smallest die in the following chain:
Ud20 > Ud12 > Ud10 > Ud8 > Ud6 > Ud4
When you roll a 1-2 on a d4 - the lowest die in the chain - the item is expended, and the Character has no more of it left.
The following table shows average uses based on the starting die within the chain.
| UD | Avg. Uses |
|---|---|
| d4 | 2 |
| d6 | 5 |
| d8 | 9 |
| d10 | 14 |
| d12 | 20 |
| d20 | 30 |
Rations and Ammunition
The most common application of usage dice within this campaign will be for rations and ammunition.
Rations
Rations will be rolled twice per day, unless otherwise foraging or paying for meals. Once at the start of the adventuring day and once at the end of the adventuring day.
Other rolls may be prompted due to complications at the GM's discretion.
Ammunition
When tracking the Usage Die for ammunition such as arrows and bullets, roll the Ud after the combat is resolved.