- The 13½ Lives of Captain Bluebear 1999The 13½ Lives of Captain Bluebear
- Ensel and Krete 2000Ensel and Krete
- Rumo and His Miraculous Adventures 2003Rumo and His Miraculous Adventures
- The City of Dreaming Books 2004The City of Dreaming Books
- The Alchemaster's Apprentice 2007The Alchemaster's Apprentice
- The Labyrinth of Dreaming Books 2011The Labyrinth of Dreaming Books
- Princess Insomnia & the Nightmare-colored Night-mare 2017Princess Insomnia & the Nightmare-colored Night-mare
- Weihnachten auf der LindwurmfesteWeihnachten auf der Lindwurmfeste
Series