bitbetter, for now i want try to keep anonymous play via tor. and black/white listing by IP address will eliminate it. Will see. If people start abuse it - I will start blacklisting. But I hope I will not need it.
I have always thought about perhaps maybe a captcha system of some sort...?
Well, obviously not a captcha, nobody would play there lol ... but something that can dissuade bots from playing? Like constantly changing the colors of the buttons you clikc perhaps?
If you held AA then the call button could be a varation or a picture of two aces, but always different, so that a human could read it but not a bot.
Just an idea.
Good luck with the site.