Sword Art Online: Progressive is the main title for the Progressive film and novel line set within the Sword Art Online universe. It retells the early Aincrad storyline with a more detailed, floor-by-floor approach, focusing on Kirito and Asuna's progress through the deadly floating castle. The series expands on events only briefly covered in the original Sword Art Online story, adding new characters, deeper worldbuilding, and a more character-driven look at survival in the game.