Radiation is a deadly threat to those who would explore technological ruins or ruins of advanced civilizations, and even in areas that appear devoid of strange artifacts, the land, the water, or the local flora and fauna may be irradiated. At the GM's discretion, adventurers may even be affected by the cumulative effects of mild levels of radiation that would be harmless if encountered briefly, but may build into dangerous levels over sustained or repeated periods of exposure.

Radiation is a poison effect, whose initial effect causes Constitution drain and secondary effect causes Strength damage. Radiation dangers are organized into four categories: low, medium, high, and severe.

Area of Effect: Radiation suffuses a spherical area of effect that can extend into solid objects. The closer one gets to the center of an area of radiation, the stronger the radiation effect becomes. Radiation entries list the maximum level of radiation in an area, as well as the radius out to which this radiation level applies. Each increment up to an equal length beyond that radius degrades the radiation strength by one level. For example, a spherical area of high radiation with a radius of 20 feet creates a zone of medium radiation 21 feet to 40 feet from the center in all directions, and a similar zone of low radiation from 41 to 60 feet.

Initial Effect: Radiation initially deals Constitution drain unless the exposed character succeeds at a Fortitude saving throw. A new saving throw must be attempted to resist radiation's initial damage each round a victim remains exposed to it.

Secondary Effect: Secondary effects from radiation deal Strength damage at a much slower rate than most poisons. This secondary effect ends only after a character succeeds at two consecutive Fortitude saving throws to resist secondary radiation damage. If a character has Strength damage equal to his current Strength score, further damage dealt a secondary effect is instead Constitution damage.

Removing Radiation Effects: All radiation damage is a poison effect, and as such it can be removed with any effect that neutralizes poison. Ability damage and drain caused by radiation damage can be healed normally.

Radiation Damage

Radiation Level Fort Save Primary Effect Secondary Effect
Low 13 1 Con drain 1 Str damage/day
Medium 17 1d4 Con drain 1d4 Str damage/day
High 22 2d4 Con drain 1d6 Str damage/day
Severe 30 4d6 Con drain 2d6 Str damage/day