49 books • 26 series
Riff Raff The Mouse Pirate (I Can Read Level 1) (I Can Read Level 2) (I Can Read Books: Level 2)
Riff Raff Sails the High Cheese (I Can Read Level 2) (I Can Read Level 1) (I Can Read Books: Level 2)
Space Dog Jack (Hello Reader! Level 1 (Paperback)) (Hello Reader!) (Hello Reader! Level 1 (Prebound))