Successfully complete campaign mode on the medium difficulty setting to unlock the hard difficulty setting.
Gray Alien in multi-player mode
Successfully complete campaign mode on the hard difficulty setting to unlock Gray Alien in multi-player mode.
Know Something We Don't?
You can submit new cheats for this game and help our users gain an edge.
Have We Been Fooled?
You can submit a problem report for any non-working or fake code in the lists above.