[This puzzle comes from the playoffs for the Sudoku Grand Prix that were held in Kraków, Poland in late 2022. Unlike last year’s World Sudoku Championship, which had no “Classic” Sudoku selected for the final playoffs, the Sudoku Grand Prix had three different classic sudoku among the eight total puzzles including one of mine. While my GP competition set had all used an “eight” theme, I did not repeat that at all here for my playoff puzzle options. My main goal in constructing this was to make a top-level “Snyder Sudoku” — as one of the competitors would call it — where (spoiler for hidden theme and solving path) the very first step is the hardest step. In this case, there is single special pattern to observe in the mostly full rows/columns that will eventually force a number in the center box. The top solve of this puzzle was achieved by Timothy Doyle of France (amazingly in 93 seconds) with several other solves in the 2-3 minute range.]
or solve online (using our beta test of Penpa-Edit tools)
Author/Opus: This is the 444th puzzle from Thomas Snyder, aka Dr. Sudoku.
Estimated Difficulty: 3 stars
Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in our e-store, including in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.