Blade of Damnation

Casting this spell causes a brilliant flash of light that coalesces into a massive sword.

this sword swings through a thirty-foot cone, making attacks against any creature in that area, upon a successful hit, the target takes 4d6 slashing damage, 1d8 crushing damage and 8d6 radiant damage( 8d10 vs. undead, and fiends). creatures of the size large or smaller affected by this spell must make a reflex save or be knocked prone.

it deals 2 additional dice of radiant damage for every slot level above fifth.

if you are at one hitpoint, this spell does maximum damage.