バトル・ロワイアル (Battle Royale) influenced 오징어 게임 (Squid Game)

Hwang Dong-hyuk has said he wrote the first version of the script in 2008 after reading Japanese survival game comics, naming Battle Royale among them, and that he wanted to make a Korean one. What he kept is the premise rather than the tone:

• A closed arena, a fixed cast, and a rule that only one of them leaves
• Rounds announced by an unseen authority, with the running count of the dead as the structure
• An ordinary social relationship reused as the alliances: classmates there, debtors here

The difference is who runs it. Takami's is a state programme, Hwang's is a private entertainment sold to the rich, and that swap is the whole of the show's argument.