Il-nam teaches Gi-hun what gganbu means
Holding their bags of marbles, Il-nam explains that a gganbu is the friend you share everything with, and the two seal it with a handshake.
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#marbles
5 moments.
The rules land: take all ten marbles from your partner
The announcement reveals that partners must play each other for all ten marbles, and the pairs realise what winning means for the loser.
Gi-hun tries to get Il-nam declared out, then begs him to play
Gi-hun tells a guard the old man has dementia, then explodes that they will both be killed, until Il-nam quietly agrees as long as he stops yelling.
Deok-su wins the hole game with one marble to spare
Deok-su's partner thinks he has won until a last marble appears; Deok-su sneers goodbye as the loser is taken away.
Sang-woo hands in twenty marbles, no harm done
Sang-woo presents both sets of marbles to a guard and notes that the rules forbid violence, which he was careful to avoid.