Bloody sharpnel

You cut your hand taking 1d8 points of damage then hold it up to release a blast of hardened blood.. Each creature in a 60-foot Cone originating from you makes a Constitution saving throw, taking 3d8 necrotic damage on a failed save or half as much damage on a successful one. 

Using a Higher-Level Spell Slot. The damage increases by 1d8 for each spell slot level above 2.