Uppercut Technique

[Kromm]

Also in the real-world technique, most of the power is generated through upward translation from a lower to a higher stance, substantially engaging the strong leg muscles. This is as opposed to using the whole body torsionally or, worse, using just the arms. Using the legs in this way gives the uppercut power comparable to a kick. Relatively few punches can compete until you get into things like superman punches, which GURPS would call a Committed Attack if not an All-Out Attack.

Game-wise, the technique is built as a punch with -2 to default for +1 to damage, and +1 to default for limited target selection (upper body of standing foe), for a net default of -1.