Rule
Usage Die are used to represent consumable or limited Resources, such as ammo or coins. Usage Die can be d4s, d6s, d8s, d10s, d12s and d20s (expressed as Ud4, Ud6, etc.).
When you Tap a Resource, the usage die is rolled. If the roll is 1-2 you Deplete the resource. When you do, you successfully use the resource, but the Usage Die is downgraded to the next lower die in the following chain:
Ud20 → Ud12 → Ud10 → Ud8 → Ud6 → Ud4
- If you Deplete a Ud4, you fail to use the resource and the resource is Exhausted and disappears.
- Certain rules allow you to Replenish a Resource, restoring it to its original Usage Die.