BTOOOM!

Ryouta Sakamoto, a top player of the online video game Btooom!, is found stranded on an island with a small green crystal in his hand and no memory of how he got there. Similar to the game, the island has a twist: a real-life version of Btooom! has been created, where players must kill seven others and collect their crystals to escape. Ryouta, initially opposed to violence, is forced to adapt when he encounters aggressive players. Alongside Himiko, a fellow Btooom! player, he tries to uncover the truth behind this deadly game.