Combust

A sudden eruption wreathes intense flames around a creature you can see in range. The target and any creatures within a 20-foot-radius must make a Dexterity Saving throw. A creature takes 6d6 fire damage on a failed save or half as much damage on a successful one. If the initial target fails its saving throw it continues to burn, taking an additional 4d6 fire damage at the start of each of its turns unless a creature uses an action to douse the flames, ending the spell. Until the spell ends the target radiates light in a 20 foot radius and dim light in an additional 20 foot radius. It also negates benefits from being invisibile.