Any game that involves diplomacy needs to be played anonymously to prevent that sort of stuff. Not just pre-existing friendships, but people you play with frequ

Any game that involves diplomacy needs to be played anonymously to prevent that sort of stuff. Not just pre-existing friendships, but people you play with frequently will learn your habits and tells, and will refuse to cooperate with someone they know is good at the game. It was easy to fix in the play-by-email Diplomacy days where you could create a new email address for each new match, but it's a lot harder in today's era of voice-chat-enabled social deduction games.