A spook spell enables the illusionist to play upon natural fears to cause the subject creature to perceive the spell caster as someone or something inimical. Without actually knowing what this is, the illusionist merely advances threateningly upon the subject, and if a successful saving throw versus spell is not made, the creature will react by rapidly turning and fleeing in as opposite a direction from the illusionist as possible (effects as a wand of fear, though items carried are not dropped). Although the spell caster does not actually pursue the fleeing creature, a phantasm from its own mind will do so. However, each round after the initial casting of the spook spell the creature is entitled to another saving throw, and each such saving throw is at a cumulative +1 per round, until the subject sucessfully saves versus spell and the spell is broken. In any event, the spell will function only against creatures with intelligence of not less than 1.