"And who set the rules for the universe?"
I think you assume to much with the question word "who." A more correct question would be "what." And the answer would be that I don't know.
Though I suspect that the rules of nature are an inherent property of the universe. Like the reason why water melts at 0 degree celsius under 1 atm. That happens because of the molecular shape of water. And the molecular shape is what makes water water. You cannot
separate water from melting at 0 C. Likewise, one cannot separate the universe from the inherent properties within it.
Though I admit that this is just speculation.