This spell could be cast on any flat surface.[note 1] The actual material of the surface was not important; stone, wood, dirt, etc., as long as it was solid. Whenever the surface was stepped on or touched by a creature larger than a typical rat (3 lb/1.4 kg or 0.5 ft3/0.014 m3) the enchanted surface would squeak loudly enough to be heard 100 ft (30.5 m) away. The sound could be heard and direction determined regardless of doors, walls, floors or other interposing barriers. Even creatures who could move silently were only able to halve the distance the sound traveled.
In addition to verbal and somatic components, this spell required a rusty iron hinge that squeaked as a material component.
- ↑ The source states the area of effect in two different ways. In the spell summary it says a "10-foot square/level" but in the spell description it says "a square whose sides equal the caster's level times 10 feet" which is considerably larger.