The Flame of Frenzy

The alien power of the Frenzy wells up inside of your eyes, using them as windows into the inner realms and bursting forth as searing purple flames. Each creature in a 15-foot cone must make a Dexterity saving throw. A creature takes 5d6 fire damage on a failed save, or half as much damage on a successful one. 

The considerable power the Frenzy holds and the ease with which it is summoned comes with a price. Whenever you cast this spell you must make a Constitution saving throw with a DC equal to 10 + the level of the spell slot used. Upon a failure, you are embraced by the Frenzy's grip, displayed by black smog pouring from your mouth and a violet glow from your eyes. While you are Frenzied, magical healing has no effect on you, and spell slots spent on healing you are wasted. In addition, you take an extra die of damage from all sources. This condition can be removed by completing a long rest or by the Remove Curse spell.

The purple fire ignites any flammable objects in the area that aren't being worn or carried.

At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher, the damage increases by 1d6 for each slot level above 1st.