68 books • 17 series
Book #1: Monsters in the Dark
Book #2: Monsters go to School
Book #4: Billy and the Mini Monsters Monsters on a Plane
Book #9: Monsters at Halloween
Book #10: Monsters go Camping
Book #4: Fairy Ponies Pony Princess
Book #6: Fairy Ponies Unicorn Prince
Book #5: Christmas Mystery
Book #2: Billy and the Mini Monsters Monsters on the Move
Book #2: Billy and the Mini Monsters Monsters go Party