By means of this spell, the wizard is able to place another spell upon his person so that the latter spell will come into effect under the conditions dictated during the casting of the contingency spell. The contingency spell and the spell it is to bring into effect are cast at the same time (the one-turn casting time indicated is the total for both castings).
The spell to be brought into effect by the prescribed contingency must be one that affects the wizard's person (feather fall, levitation, fly, feign death, etc.) and be of a spell level no higher than 1/3 of the caster's experience level (rounded down), but not higher than the 6th spell level. (See book for table ).
Only one contingency spell can be placed on the spellcaster at any one time; if a second is cast, the first one (if still active) is cancelled. The conditions needed to bring the spell into effect must be clear, although they can be rather general. For example, a contingency spell cast with an airy water spell might prescribe that any time the wizard is plunged into or otherwise engulfed in water or similar liquid, the airy water spell will instantly come into effect. Or a contingency could bring a feather fall spell into effect any time the wizard falls more than 2 feet. In all cases, the contingency immediately brings into effect the second spell, the latter being \"cast\" instantaneously when the prescribed circumstances occur. Note that if complicated or convoluted conditions are prescribed, the whole spell complex (the contingency spell and the companion magic) may fail when called upon.
The material components of this spell are (in addition to those of the companion spell) 100 gp worth of quicksilver and an eyelash of an ogre mage, ki-rin, or similar spell-using creature. In addition, the spell requires a statuette of the wizard carved from elephant ivory (which is not destroyed, though it is subject to wear and tear), which must be carried on the person of the spellcaster for the contingency spell to perform its function when called upon.