A collection of over 100 variant sudoku puzzles set by 22 constructors. Each puzzle solves uniquely. Puzzles can be solved online using provided links. The book also contains an introduction to variant sudoku and to the online solving platform. Constraints and constraint combinations include cages, German Whispers, Dutch Whispers, Zipper Lines, arrows, consecutive and ratio pairs, XV dominoes, modular and entropic lines, and more.