Dragon Tail

Upon being attacked by a flanking enemy, as a reaction, you spin your body violently, much like a dragon would if it was attempting to tail slap an attacker. In response, a roiling tail of energy based on your dragon ancestry lashes out at the flanking attacker. This spell deals 1d10 per spell slot used + Charisma modifier damage and knocks the target away from you 10 feet per level of the spell slot used. The target also falls prone. If the target is knocked into a stationary object, the target takes 1d6 appropriate damage, (bludgeoning, slashing, piercing, fire, etc), depending on what it collides with. The caster chooses what direction the target is knocked back.