Tome of Magic Version[]
Miscast magic can be cast only on a wizard. It causes the next spell cast by the affected wizard to be chosen randomly from his memorized spells of the same or lower level. Thus, if a wizard affected by miscast magic had four 1st-level spells memorized ( armor, feather fall, jump, and sleep) and he attempted to cast the sleep spell, the DM would determine the resulting spell randomly from the wizard's four memorized spells. The wizard has only a 25% chance of casting the sleep spell.
Only spells currently memorized are eligible to be exchanged with the desired spell. If a wizard had only one spell memorized, the miscast magic would have no effect and the wizard's spell would be cast normally.
The miscast spell operates normally. If a wizard tried to levitate a companion but a web spell resulted, the companion would be trapped by the webs and subject to all resulting effects. If the target of the spell were in range of the levitate spell but not in range of the web, the spell would be lost in a fizzle of energy and the web spell would be wiped from the caster's memory.
The wizard who casts the spell performs the proper verbal and somatic components of the spell he wishes to cast; he does not discover the altered results until the wrong spell takes effect. The wizard will also discover that the material component for the resulting spell has vanished (in addition to the material component for the desired spell).
Wizards who are targets of miscast magic are allowed a saving throw vs. spell to avoid the effect.
Priest's Spell Compendium Version[]
Miscast magic can be cast only on a wizard. It causes the next spell cast by the affected wizard to be chosen randomly from his or her memorized spells of the same or lower level. Thus, if a wizard affected by miscast magic had four 1st level spells memorized (armor, featherfall, jump and sleep) and attempted to cast the sleep spell. the DM would determine the resulting spell randomly from the wizard's four memorized spells. The wizard has only a 25% chance of casting the sleep spell.
Only spells currently memorized are eligible to be exchanged with the desired spell. If a wizard had only one spell memorized, the miscast magic has no effect and the wizard's spell is cast normally.
The miscast spell operates normally. If a wizard tried to dilate a companion but a web spell resulted, the companion would be trapped by the webs and subject to all resulting effects. If the target creature was in range of the levitate spell but not in range of the web, the spell would be lost in a fizzle of energy and the web spell would be wiped from the caster's memory.
The affected wizard performs the proper verbal and somatic components of the desired spell; the altered results occur when the wrong spell takes effect. The wizard will also discover that the material component for the resulting spell has vanished (in addition to the material component for the desired spell).
Wizards who are targets of miscast magic are allowed a saving throw vs. spell to avoid the effect.
Notes: Common for priests with access to the sphere of Chaos (ToM).