Eldritch Strike

Eldritch energy crackles and flows around your hands for the duration. Make an unarmed strike against a target before the end of your next turn. On a hit, the target takes the your normal unarmed strike damage as well as 1d8 force damage. The spell will continue even after striking your target as long as the duration is not over.

The spell lasts longer when you reach higher levels: two rounds at 5th level, three rounds at 11th level, and four rounds at 17th level.