You'll get 20 credits each time, you can just let it run in background and do other stuff (or overnight) and you'll easily manage to make a few hundred/thousand credits in the meantime. It's probably the best possible way to autofarm on this game anyway, unless someone who has a lot of time comes and does a whole thing to automatically place towers during the game etc. (and I'm not even sure about it tbh since winning a game would take around 30 minutes from what I know and you wouldn't even win much more, maybe even less than what you'd win using the script). Make sure you have "auto-attach"