Syrus Truesdale, known in Japan as Sho Marufuji (丸藤翔, Marufuji Shō), is a former Slifer Red, then Ra Yellow, and now Obelisk Blue (briefly in season 3, but permanently in season 4) student as well as Jaden's best friend. A decent Duelist, although hindered by a great deal of self-doubt, though this mainly stems from his brother Zane's treatment of him, Syrus' journey towards strengthening himself provides sharp contrast to the protagonist Jaden's active determination.