From the back of the book:
A place where young wizards study
This book "School Maze" is a sourcebook containing additional rules and data for "Night Wizard! The 2nd Edition". The 4 new classes mutant, alchemist, samurai, taoist are added, and additional special abilities for the classes that have existed thus far have also been prepared. In addition, it adds spells and magic items and the like that are useful when exploring fortresses.
Challenge the gekkou that have become mazes
The book adds rules for handling "fortresses", maze-shaped gekkous and data for traps and enemies and the like, and it also contains rules for random fortress generation. And, as an establishment for using these rules and data, the Kimei campus has been prepared. Young wizards! Challenge the giant maze "School Maze" stretching out under the ground of the campus!
The campus maze waits for you