Delayed Blast Fireball

A variant on the fireball spell, a sufficiently powerful fire scholar may ensorcel a room so that after a given amount of time has passed, a fireball will detonate in a room. While more powerful scholars may have more than one fireball placed at once, when the caster has reached his limit, he will in general not be able to place another for an additional two and a half hours beyond the duration of the delay. This spell cannot be cast on or under water.

Delays must be 0 or greater. A delay of 0 does not mean the spell will be cast immediately, but rather at the next half hour that passes.