Elven Pebbleslayer

You create a magical hammer of fire, shaped like a Dwarven Thrower, and hurl it at one creature within 120 feet. On a successful strike, the hammer deals 6d8 fire damage to the target. The hammer then explodes and any creature within 5 feet must make a dexterity saving throw. On a failed save the target takes an additional 4d8 fire damage and being caught on fire. On a successful save the target takes half damage and is not caught on fire. Any other creature within 5 feet takes 4d6 fire damage and is caught on fire on a failed save. On a successful save they take half damage and are not caught on fire. If any creatures are caught on fire they take 1d6 fire damage on the beginning of their turn and it takes an action to put out the fire.

At Higher Levels. When you cast this spell using a spell slot of 6th level or higher, the immediate damage increases by 1d8, the explosion damage increases by 1d8 for the target and 1d6 for any creature within 5 feet for each slot level above 5th.