Code a way to control the net to catch the robots before they drift away. One method is to use the Scratchlink extension to connect the net sprite to your Microbit and tell the net to move (change +/-x, change +/-y) when tilting is detected.
A big thank you to kids who came to MakerKids early on Feb. 6, 2018 to watch the Falcon Heavy launch with us. Your excellent questions about robots (or Tesla cars) floating away in space inspired this game! Video of the launch can be viewed at the link below. https://www.youtube.com/watch?v=sB_nEtZxPog