Do you receive any error codes or black screens? Have you installed all the latest Windows Updates and Drivers? Are you playing on a public or private network? Do you have any antivirus software installed? Are you running the game as administrator?
Nothing happens. I just click on the launcher, or the exe, and nothing happens. No errors. It just doesn't even start the patcher or anything. I'm on my home network. Latest version of Windows 11. I do have an antivirus, though. BitDefender
Fresh install of Windows? Have you tried re-installing Rumble Fighter? Weird, you can also try disabling BitDefender.