Sunbeam

You call forth one beam per 2 caster levels instead of per 3. The damage dealt increases to 4d8 points of damage. The damage dealt to undead creatures, fungi, mold, oozes, and slimes increases to 1d8 points of damage per caster level (maximum 20d8). Any creature that successfully saves against a beam is dazzled for 1 minute.

Augmented (9th): If you expend three uses of mythic power, the first beam you create has a duration of 1 round per 2 caster levels, and deals maximum damage on the round you cast it. Creatures in the beam can attempt saving throws to avoid blindness, but not the spell's damage.