Arcane Arrow

A thrumming arrow of glowing magical force streaks unerringly toward a target within range, piercing it and vanishing in sparkling lights. The target must make a Dexterity saving throw, taking 4d6 + 16 force damage on a failure. On a successful save, the arrow grazes the target and inflicts half the damage. 

• If the target fails their saving throw with a natural roll of 1 or 2, or if they automatically fail dex saving throws, extra damage is inflicted as though it were a critical hit (doubling the damage dice), and the Shield spell ends on the target. 
• The target receives no benefit from the Evasion feature if they fail their saving throw. (All or nothing)
• Optional Rule: You may target a foe you cannot see if you are aware of their location through sound, misty outline, or otherwise, but they gain advantage on their save, and cannot be crit even if they automatically fail. 

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 + 4 and the range increases by 50 ft for each slot level above 3rd (with a maximum range of 300 ft)