Agni's Whirlwind Inferno

You call forth a flaming typhoon in a 15-foot-radius, 60-foot-high cylinder centred on a point within range. Until the spell ends, it produces 30 feet of bright light and 30 feet of additional dim light from the spell's edge. Any range attack that passes through this area, is at disadvantage until the spell ends, and if a non-magical flammable object, that is not on a creature, is caught in the area, it is immediately disintegrated. While the caster is within the spells area of effect, they gain immunity to fire damage. Whenever a creature enters the spell area or starts its turn in the area, they must make a Dexterity saving throw. On a failed save, it takes 10d8 fire damage, or half as much on a successful one. On each of your turns after you cast this spell, you can use an action to move the spell 25 feet in any direction.

At Higher Levels: When you cast this spell using a spell slot of 8th level or higher, increase the damage by 1d8 per slot level above 7th.