Dreadknight's Revenge

You are cloaked in a heavy suit of infernal plate. You gain 30 temporary hit points for the duration and you may only move at half speed. The armor explodes in a forceful display, dealing 30 points of force damage to every creature within a 10 ft sphere when your temporary hit points are reduced to zero. Add 1d10 of force damage for every enemy strike used against your temporary hit points.

Each creature effected by this spell must succeed a strength saving throw vs your spell DC or be knocked prone.