THIS WAS GRAPHIC!! Twins React To Alice In Borderland S2x6!!! 

As was suggested earlier and as we see here the Citizens are former players, so not apparently real game masters, even if they create games they can die in them. They face off against the normal players in the face card games. Just like the dealers from series one it's one side against another. The numbers game needed some clever guessing, but we saw that it boiled down to much more than that. Sometimes people do apparently lose by lack of strength or cleverness, but as we also see sometimes people are just willing to die, and happier doing that. Player or Citizen may be like that but as you say it doesn't make sense just playing a game forever to survive. The former no 2 at the Beach also had a flashback which showed him meeting that guy who survived from the tunnel game. He seemed to refer back to the tunnel game and how he was helped. Indirectly you could say Arisu saved Chishiya.

Yeah,.... let's goooooooooooooooooooooooo!!!!

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