Bursting Demon Fang

The user takes the force and power of demon fang and attempts to draw it in and keep it inside the weapon instead of unleashing it out but the attempted process is a failure as the energy rips out of the weapon causing damage (4D6 force) to anyone that is within the radius(20ft) of the blast which is centered at the user. anyone caught in the blast must make a Dex saving through or be hit by the energy that rips out of the weapon. in the process of the energy breaking out the weapon used is destroyed unless it has a property that prevents it. 

Prerequisite: Must Know the Demon Fang Cantrip to learn this spell.