War Hammer of Will

Waving your hands, you manipulate the light around you and within you to create a War Hammer of Radiance. This hammer deals the damage that of a normal war hammer, but with the added damage of 2d6 radiant damage.

If you roll a natural 20 with this weapon, the creature that you hit with this weapon will be pushed back 15ft from you and doubles the radiant damage dice.

if you're proficient with the war hammer or the weapon type this weapon is, then you also get to add the proficiency modifier to your attack roll and to your total damage.

This spell will increase by 2d6 per spell level.