Algade Showdown (アルグードの決闘, Arugūdo no Kettō?) is the sixth Material Edition of the Sword Art Online series. Kawahara Reki published it under his pen name Kunori Fumio. It was sold at COMITIA 90 on November 15, 2009. It features the story of Asuna and Kirito trying to solve the mystery of whether a certain cook was a Non-Player Character (NPC) or a player.