58 books • 17 series
Project X CODE Extra: Purple Book Band, Oxford Level 8: Wonders of the World: See the Sights! (Project X CODE Extra)
Project X CODE Extra: Purple Book Band, Oxford Level 8: Pyramid Peril: Pyramid Secrets (Project X CODE Extra)
Project X Origins: Lime Book Band, Oxford Level 11: Trapped: Escape Artists (Project X Origins)
Project X Origins: Orange Book Band, Oxford Level 6: Invasion: Body Invaders (Project X Origins)
Project X Origins: Gold Book Band, Oxford Level 9: Head to Head: Game On! (Project X Origins)
Project X Origins: Dark Blue Book Band, Oxford Level 15: Top Secret: The Spy's Secret Handbook (Project X Origins)
Project X Origins: Grey Book Band, Oxford Level 13: Great Escapes: Escape from Colditz (Project X Origins)