1. Polymorphism
The old man in the series played role in many forms as the creator, player and the host of the game.
2. Inheritance
All players inherit the same parent properties like dress code, food, tasks. With that we can have different players with different playing strategical methods.
3. Encapsulation
Squid games itself is a big encapsulation combination of frontman, VIP, Host, Players, Money (consider as variables). Tasks(consider as functions) makes the squid game.
4. Abstraction
Though everyone performs the tasks no one knows the process behind them. From soldiers, moto to the behind the scenes of preparing everything for the task, which are all hidden.