
Squid Game Season 3 ended with Player 456's ultimate sacrifice, and there was a deeper meaning behind his tragic fate. After he won the games in Squid Game Season 1, Seong Gi-hun (Lee Jung-jae) was hellbent on putting an end to it all, mainly to prevent more deaths and stop an inhumane system. This is why Gi-hun returned to the games in Squid Game Season 2 despite already being a billionaire in the outside world. His efforts were thwarted by the Front Man after he infiltrated the games as one of the players, which brutally ended the player rebellion Gi-hun orchestrated from the start.
Squid Game's final season on Netflix began with a defeated Gi-hun, who appeared to have lost his purpose in life after failing with the rebellion and losing his best friend, Jung-bae. Season 3's early moments showed a version of Gi-hun who did not care anymore and someone who embraced his dark side after killing Dae-ho (Player 388) during the hide-and-seek game (he killed him because he blamed him for the failed rebellion after not bringing back the guns' magazines during the uprising). However, he ultimately redeemed himself in the end after bearing the responsibility of caring for Jun-hee's (Player 222) baby in the latter rounds.
The final season of Netflix's South Korean thriller series continues Gi-hun's journey as he is pushed to the limit by the Front Man and the VIPs to try to convince him that there is no more hope to humanity. Squid Game Season 3 boasts a star-studded cast led by Lee Jung-jae, Lee Byung-hun, Kang Ha-eul, Yim Si-wan, Jo Yuri, Wi Ha-jun, and Park Gyu-young.
Why Did Player 456 Kill Himself?

One of Squid Game Season 3's darkest twist revolved around Jun-hee's baby becoming a contestant (Player 222) after her mother's death in the fifth game, meaning that the newborn became an instant target for the other cruel players in the final round, the Sky Squid Game.
Gi-hun, who promised Jun-hee that he will take care of the baby, fought tooth and nail to protect the newborn, leading to a final confrontation with the baby's father, Myung-gi (Player 333). Myungi-gi's desperation for survival and greed ultimately led to his tragic downfall in Squid Game Season 3. After his death, the remaining players in the final round are Player 456 and the baby, but only one must survive and become the winner according to the rules of the game.
By taking care of the baby, Gi-hun found a renewed sense of purpose in life, which is why he decided to kill himself in the end by falling off the platform to save the baby (making the newborn a winner of the Squid Game as well).

Player 456's act of sacrificing himself also made him a hero in Squid Game Season 3 since he proved the Front Man and the VIPs wrong that there is still some hope for humanity despite the existence of cruel and desperate individuals who only wanted the prize money for themselves.
His final statement about humans not being horses that they can just use as bets for their entertainment also resonated with the Front Man, as evidenced by his future actions of helping Gi-hun's daughter to start fresh with his remaining prize money and ensuring the baby's safety in the outside world. In a way,
Squid Game Creator Explains Gi-Hun's Sacrifice

Gi-hun's sacrifice in Squid Game Season 3 came full circle for the character since he initially started as a deadbeat gambler in Season 1. As his journey progressed, it became clear that Gi-hun is a noble man who only wanted to put a stop to the brutality and cruelty of the games and its organizers. Unfortunately, it came down to the cost of his life.
Speaking with TUDUM, Lee Jung-jae explained why Player 456's decision to kill himself made sense for the character, noting that he did that because "it is almost like Gi-hun's looking at his own daughter" right before his sacrifice.
For those unaware, Gi-hun has a daughter in the outside world, but his continued attempt to stop the games led to his estranged relationship with her.
Meanwhile, Squid Game creator Hwang Dong-hyuk spoke with The Hollywood Reporter to give his thoughts about Gi-hun's sacrifice and the ending, noting that the baby's presence allows the series to show "a more accurate degree [of] the rock-bottom of humanity" while also shedding on light on an "even brighter hope:"
"Since it is the finale, I thought that raising the stakes and taking a bigger risk in true Squid Game fashion was the right way to go. Through that, I wanted to expose to an even a more accurate degree the rock-bottom of humanity and also shed light on even brighter hope. I believe that through the baby, Gi-hun is able to show those themes in a more detailed way."
The series creator also explained the deeper meaning behind Gi-hun's actions, pointing out that it sends a message that he "wants to give a better world to our future generation," with the baby representing the latter:
"I believe that all of us are able to live in this world the way we do due to the efforts and struggles that our previous generation went through in order to give us a better world. And the reason we need to try to right the course of the world is because we want to give a better world to our future generation. So in our story, the baby not only represents human conscience, but also the future generation for whom we need to fix the way we are."
In the end, Gi-hun's decision to kill himself fulfilled his promise to Jun-hee that he will protect the baby no matter what. While he was not around anymore, his sacrifice impacted those around him, particularly the Front Man, in ensuring that the baby has a bright future ahead.