Void Bite

You make a ranged spell attack at a creature within range. On a hit you deal 2d4 void damage. Any d4 that rolls a 4 is added to the total and then rolled again. This process can repeat as many times as necessary until no dice land on a 4. 

The number of d4's you roll increases at certain levels. At 5th level 3d4, at 11th level 4d4, and at 17th level 5d4.

If this spell deals 20 or more damage in a single casting the target is afflicted with the Fading condition.