Great thunderclap

Great thunderclap was a spell used by sorcerers and wizards.

Effects
When cast, the spell created an incredibly loud noise identical to a lour thunderclap. Along with the sound, the spell created a powerful shock wave that stunned any creature within a radius. This area spread as the caster's skill level increased.

Components
In addition to verbal and somatic components, the spell required a focus, a bell made from iron.