First, get a Microchip from your Tools Bag, then, insert it into a Sackbot's circuit board, then, put 2 player sensors (both of them must be on 180 angle detection, one to the left, and the other to the right), then put a grab sensor, get 2 AND gates and connect the grab sensor to both of the AND gates, connect the left player sensor to the left AND gate, and the right player sensor to the right AND gate, then put 2 Sackbot Behaviors, seth both of them to Act and record the left one to make it punch to the left REALLY QUICKLY (0.1 seconds aprox.) and the right one to the same thing but to punch to the right side, then connect the left AND gate to the left Sackbot Behavior and the right AND gate to the right Sackbot Behavior, then put a Timer set to 0.1 aprox. and connect it to the main Sackbot Behavior in the Sackbot's circuit board and ta-da!

Sounds cool ( u could make a warrior or something with that )

Hahaha! Ive never thought of making a slaping sackbot! Good job :3