Sunbeam

For the duration of this spell, you can use a standard action to evoke a dazzling beam of intense light each round. Each time you evoke a beam, the spell's duration is reduced by three rounds. Each creature in the beam is blinded (permanently) and takes 4d6 points of damage. A successful Reflex save negates the blindness and reduces the damage by half. An undead creature caught within the beam takes 1d6 points of damage per caster level (maximum 20d6), or half damage with a successful Reflex save.