Destruction Of The Oni

Create a blast of massive destruction from the power of the Oni, masters of destruction. This spell does 8d10 necrotic damage.
If you hit a celestial being with this spell, it does an extra 2d8 Force damage. The celestial being then has disadvantage for 3 turns. 
If you hit a dragon with this spell, it does an extra 3d8 necrotic damage. The dragon then is Proned for 2 turns.