Disease
(Illusion/Phantasm)

Range:  30 yards
Components:  V, S
Duration:  Special
Casting Time:  2
Area of Effect:  One creature
Saving Throw:  Negates

Similar to spells such as blindness and deafness, a disease spell will cause its target to believe that he has contracted a real (natural) disease. Even though the spell affects the mind, the victim believes so strongly in the disease that boils, pains and any other symptoms normally associated with the affliction will be imagined, putting the individual's health under considerable stress.
If the target has recently been in a situation where contracting a disease is quite likely (such as living in filthy surroundings, falling into sewage or garbage heaps, attacks from giant rats or otyughs, etc.), a saving throw is made at a penalty of -4; on the other hand, if a character has recently had a cure disease cast upon himself, is immune to normal diseases, or has some other strong reason to believe that he could not possibly have contracted a disease, then a saving throw at +4 or higher (probably +8 if normally immune) is allowed.
Once the spell takes effect, it is permanent until the victim receives a dispel illusion. The disease is determined randomly from the table in the Dungeon Master's Guide (q.v.), with the full effects described affecting the target.

