[Game help] impairment

When mages and priests cast offensive spells, powerful energies are put 
into play.  Even when the target is fortunate enough to save against
a devastating magical effect, the effort often leaves their protections
impaired and temporarily more vulnerable to the next such attack.

Some spells that are known to cause impairment include the following:
blindness, burning hands, cone of cold, confusion, control undead,
curse, deafness, dispel magic, domination, energy drain, fear, feeblemind,
interdiction, lightning bolt, magma spray, persuade, petrification, plague,
poison, shocking grasp, sleep, slow, weaken

If you are impaired, your saving throw against that type of attack is
temporarily degraded.  For example, if you make a saving throw against
poison, your fortitude save will be lowered temporarily, making you more
vulnerable, not only to additional poisoning, but also finger of death. 
Likewise, feeblemind spells can impair willpower save and shocking
grasp can impair reflex save.

Follow-up spells that still fail will further degrade the associated saving
throw. But impairment will only occur for as long as the target still has 
a saving throw bonus.  Targets that have no bonus to their saving throw
from buff spells or endowed items are at no risk of impairment.

Spells triggered via the use of an item will also not cause impairment.

See also: saves