5th Level Wyrd Evocation (named)
Casting Time: 1 action
Range: 18 sqr. (36m)
Components: V, S
Duration: 1 minute, concentration
You envelop a creature you can see within range in dark flames that burn inward, growing hotter with each passing moment. The target must make a Dexterity saving throw. On a failed save, the target takes 4d6 fire damage and 4d6 necrotic damage and is ignited in magical flames for the spell’s duration. On a successful save, the target takes half as much fire damage and is not ignited, the flames do not intensify.
While ignited, the target sheds bright light in a 6 sqr. (9m) radius and dim light for an additional 6 sqr. (9m). These magical flames can’t be extinguished by nonmagical means.
At the end of each of the target’s turns, it must repeat the Dexterity saving throw. On a failed save, the target takes 4d6 fire damage and 4d6 necrotic damage, plus an additional 1d6 fire damage and 1d6 necrotic damage for each previous time it has failed this saving throw (the flames intensify). On a successful save, the target takes half as much fire damage (including any cumulative increases) and the flames cease.