24 books • 5 series
Book #1: Ad Astra 001
Book #9: Ad Astra 009
Book #10: Ad Astra 010
Book #11: Ad Astra 011
Book #26: Ad Astra 026
Book #75: Gg 075
Book #8: Gg 008
Book #9: Gg 009
Book #12: Gg 012
Book #13: Gg 013
Book #14: Gg 014
Book #45: Der Seher von Yys
Book #32: T 032
Book #49: T 049
Book #51: T 051
Book #53: T 053
Book #54: T 054