This is a very basic implantation of a botnet using a Python (Flask) c2 server and a Powershell client. The example command script given (win_commands.ps1) changes a victim's background to a picture of a cat on Windows computers.
Although simple and non-malicious in this form, this demonstrates the low difficulty of implementing a basic botnet. The command script could just as easily be harmful and cause damage to your computer and/or network.