Standard registration has been disabled. It's amazing how many spambots are out there.
If you want to join the Rubicon forum, just send an email to email@example.com with the subject line "Rubicon forum membership
request", stating the username you want and writing a little bit about what you thought of the game and why you want to
join the forums, and we'll sort an account out for you manually.
Sorry to be a pain, but we were
having to manually reject dozens of spambots every single day, just to let one genuine user through every month or two.