Pyroclastic Lance

You conjure a lance of blazing lava and hurl it at a creature you can see within range. Make a ranged spell attack. On a hit, the target takes 8d6 fire damage. Hit or miss, the lance then explodes in a 10-foot radius sphere of pyroclastic ash centered on the target. The ash lasts until the start of your next turn, and its area is heavily obscured. Any creature starting its turn within the ash cloud must succeed on a Constitution saving throw or take 4d6 fire damage and be blinded until the start of its next turn.