Player 278 is shown to be rude, arrogant, and vulgar. He makes a sexual joke about "being good at getting things in holes" in the 4th game and sticks his tongue out in a lewd manner at Han Mi-nyeo. He was also complicit to Jang Deok-su, until the 6th episode when he started getting cocky towards him while laughing and mocking because he couldn't resort to violence.
Player 278 was in heavy debt and decided to enter a high-risk competition to win money. After waking up in a large room with 455 other people, he signed a contract and took his photo. He managed to survive the first round. Even though he voted yes, his financial issues outside of the game encourage him to come back. During the second round Sugar Honeycombs, he was falling behind as he struggle to carve his shape. When he saw Player 456 lick his honeycomb, Player 278 and many others copy 456. He managed to carve his shape before time ran out. He joins Jang Deok-su's gang and acts as his main henchman. They recruits more men to form a team to participate in Tug of War. After winning against Team 7, he partners up with 101 in Marbles.
During the marble game he faces Player 101. In the guessing portion, 278 was being cocky as he kept guessing his opponents’ marbles correctly. 101 was furious and demanded to switch marble games to be fair. The employee approved his request and they started a challenge of tossing their marbles into a hole. They came down to their last tries and Player 278's marble hit a pebble and pushed 101's marble into the hole by accident. Player 278 freaks out and runs off to avoid being eliminated, but he runs into a dead end, screaming "You are all assholes!" before being eliminated.
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Behind the Scenes
He was portrayed by Kwak Ja-hyoung. The other 278 was portrayed by an unknown extra
- Despite his player number being clearly visible, he is credited as Deok-su's Gang Member 2.