Cursed flames

 outstretched your fingertips Each creature in sight must make a Dexterity saving throw. A creature takes 5 fire damage on a failed save, or half as much damage on a successful one. 

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

This spell last until the affected items or creatures are dead

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the damage increases by 5 for each slot level above 4th.