How to play the card killing game?

To add to the above, talk about card games. For example, 9 people, 2 policemen, 2 bandits, and 1 judge, and then choose 2 K (killer) as the killer, 2 J (policeman) as the policeman, 4 arbitrary cards, and 1 Wang as the judge. Then wash 9 cards and distribute them to everyone. Everyone can only see their identity. This is the rule. Everyone closes their eyes when it gets dark, and only the designated identity can open their eyes.