Tharn's Arrow

Conjure a spectral greatbow and shoot an arrow made of pure magic. Make a ranged attack roll on a target that you can see reaching 150ft. On hit deal 3d8 piercing damage. 

Until the spell ends, you can make the attack again without using a spell slot on each of your turns as an action.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d8 for each slot level above 3rd.