The world of Ground Zero is heavily polluted by radiation - the product of nuclear fallout from the Crash. Because many communities no longer grasp the true power of the Ancients, radiation is often misunderstood, if comprehended at all. Since it is invisible, radiation is often accorded a mystical nature, and either worshipped as a force for change and purification, or feared as a kind of lethal curse left over from long ago.
Radiation exposure often results in rad sickness, variously called "rad fever", the "red thirst", or "slow death". the effects of radiation are rarely recognized in time, and even more rarely is treatment possible with the few medical resources available so long after the Crash. By all accounts the radiation of the nuclear war will last for tens of thousands of years, and as such it poses perhaps the single most insidious threat to long-term life in Ground Zero.
When characters are exposed to radiation, they may suffer the effects of rad sickness. In addition, exposed characters gain long-term Creep contamination. The severity of rad sickness and amount of Creep varies with the radiation level and the total amount of exposure time.
Radiation levels vary from mild to low, moderate, high, severe, to lethal. The effects of radation get worse the longer a character is exposed it. The table below gives the resulting rad sickness severity and Creep gained based on radiation exposure:
| Time of Exposure | ||||||
|---|---|---|---|---|---|---|
| Radiation Level | 1 round | 1 min | 10 min | 1 hour | 1 day | Creep Count |
| Mild Radiation: | none | none | none | none | mild | 0 |
| Low Radiation: | none | none | none | mild | low | 0 |
| Moderate Radiation: | none | mild | low | low | moderate | 1 |
| High Radiation: | low | low | moderate | moderate | high | 1d2 |
| Severe Radiation: | moderate | moderate | high | high | severe | 1d4 |
| Lethal Radiation: | high | high | severe | severe | lethal | 1d6 |
Start with the radiation level of the environment that the character is in or the radiation source that he is exposed to. Next, determine the total time of exposure within a given 24-hour period, rounding up. Look at table to find the resulting severity of rad sickness.
Multiple exposures to radiation in a short period of time are not cumulative. If a character is exposed to more than one radiation source in a day, only count the highest exposure level for determining the severity of rad sickness and incremental Creep.
For Example: Behzed is exploring a ruined laboratory that has a moderate radiation level. He quickly searches the location, spending a total of 12 rounds in the irradiated area. This counts as 10 minutes at a moderate radiation level, since 12 rounds is more than 1 minute. Behzed must make a saving throw against "low" severity rad sickness. He also racks up 1 point of Creep. If he returned to the lab later that day for another 10 rounds (1 minute), he would not suffer any additional effects, since it is still less than 10 minutes exposure.
Rad sickness functions exactly like a disease, following the normal rules for diseases, except that characters can sometimes suffer adverse effects even on a successful save. The degree of the effects depends on the severity of rad sickness, as indicated on the following table:
| Severity of Rad Sickness | Fort Save DC | Incubation Period | Damage (Successful Save/Failed Save) |
|---|---|---|---|
| Mild: | 12 | 1 day | 0/1d4-2* Con |
| Low: | 15 | 3d6 hours | 0/1d6-2* Con |
| Moderate: | 18 | 2d6 hours | 1/1d6-1* Con |
| High: | 21 | 1d6 hours | 1d4-2*/1d6 Con |
| Severe: | 24 | 1d4 hours | 1d6-2*/2d6† Con |
| Lethal: | 27 | 1d2 hours | 1d6-1*/3d6† Con |
* Minimum damage is 0.
† On a failed saving throw, 1 point is permanently drained.
Note that for moderate rad sickness and worse, Constitution damage occurs even on a successful saving throw vs. disease. If a character suffers from more than one severity level of rad sickness at a time, count only the highest one.