72 books • 19 series
Project X Alien Adventures: Dark Red Book Band, Oxford Level 17: Powerless (Project X Alien Adventures)
Project X Alien Adventures: Grey Book Band, Oxford Level 14: The Waythroo Wormhole (Project X Alien Adventures)
Project X Alien Adventures: Grey Book Band, Oxford Levels 12-14: Grey Book Band Class Pack of 72
Project X Alien Adventures: Grey Book Band, Oxford Levels 12-14: Grey Book Band Mixed Pack of 12