Erupting Shard

You form a shard of volcanic rock that is charged with volcanic magic, mage a ranged spell attack to launch this shard at an enemy, on a successful hit the target takes 2d6 piercing damage. After making a successful hit the shard will be embedded into the target and on the next turn will explode spewing lava in a 20 foot radius, any creature caught in this radius must make a dexterity saving throw or take 6d6 fire damage (half as much on a successful save).

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the explosion deals an extra d6 of fire damage for each slot level above 3rd.