With Sudoku CAD you can turn any harmless easy puzzle into true evil one using powerful built-in optimizer. Manually or fully automatically create puzzles with different difficulty levels and symmetries. Save them into files. Solve by hand, get hints, modify and print. When solving by hand, intermediate snapshots can be stored and then returned to. All random puzzles have numbers so you can recreate them at any time. Puzzles are rated based on how many guesses solver had to make in order to make complete solution(s) analysis. Ability to generate puzzles with symmetries, deductive solver is improved, looks native on Windows XP.