Stealing everything you can for absolutely no reason and overpreparing without a cause, bordering on "Play to Win" mindset.
7. Do not join the server using more than one account at once.
8. Antagonists are supposed to make the round more fun, not rush to end the round for an easy win.
Antagonists are not allowed to murderbone without a good reason. That is, murder everyone they see just because. If you have to murder someone to complete your objectives or eliminate witnesses/threats, you are free to do so but within reason. Antagonist role is here to make the round more fun, yet they are not forbidden from using stealthy tactics for an easy win.
9. Metagaming and metacommunications are not allowed.
Metagaming is using information that you did not receive in-round, information from the wiki is an exception. Metacommunication is communicating with someone outside of the game to gain an unfair advantage over other players.
10. If you wish to leave the game, don't just disconnect.
Find a cryogenic freezer or a centcom teleporter to free the job slot for any future players. If you are playing as a command role or as AI, notify admins if you have to leave, as you may be an important part of the current round. Try to leave unique items in your locker before leaving the round.