You create a ghostly green radiance anywhere within range that shines with the brightness of a torch and is imbued with unearthly power, causing creatures within 30 feet to become shaken unless they succeed on a Will save.
The light can be shaped to any Medium or smaller form, and can move at a speed of 30 feet as long as you maintain concentration on the spell (so that you can shape the effect into a human form and make it seem to walk or fly, for example).
The shape of a ghost light can be changed at any time during the spell's duration as a free action.