Sword Art Online Progressive Scherzo of Deep Night, Vol. 3 (manga)

The battle against the fifth-floor golem boss begins with a bang! Titanic limbs snatch and stomp at the small party of elites Kirito and Asuna hastily brought together, threatening to eviscerate the players long before they get their hands on the flag they came for...Will their risky plan succeed? Or will rushing to complete the floor end in the worst of all ways-dead friends, a war between the guilds, and halted progress toward escaping the game?!