very powerful when you use the green rod.
Step 1: the barrel
you need 20 gray half circle pieces.6 gray one way connectors. one orange 2 way connector. 3 little black rods. 2 black one way connectors. 2 white rods. 1 90 degree connector.2 2 way connectrs (gray). and one black thing (see pic) assemble by picture. Almost forgot and six blue rods.