Descent Into Madness
More insidious and powerful than the feeblemind spell, descent into madness afflicts one creature with a random form of insanity. The spell can affect any creature with an Intelligence of low (5) or higher; however, a character or creature protected by a Mind Blank is immune to this spell. Creatures are entitled to a normal saving throw vs. spell to withstand the spell. The form of insanity caused by the spell is determined by a roll on the chart:
The caster has no idea what kind of madness the spell inflicts on its victim, although he may be able to form an educated guess after observing the victim for a few rounds. Descent into madness accelerates the process of insanity radically, producing an advanced condition almost immediately; for example, a character rendered paranoid by this spell skips past suspicion and instantly regards his friends and allies as enemies of the worst sort. The victim has a small chance of recovering with the passage of time but other than that the only ways to repair the effects of this spell are Restoration, Wish, or use of the psionic power Psychic Surgery.
Material, Somatic, Verbal
The material component is a special cube of gold wire worth at least 500 gold pieces shaped to represent a tesseract, or four‑dimensional figure.