Since 2021, we have posted some extra difficult Sunday Stumpers, about once a month. These will be quite tough puzzles, but with a logical path to be found (and solution videos to help). This sixth Sunday Stumper of 2022 is a combination of Battleships and Sudoku by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between number placement, ship placement, and shading modes. The shading mode in gray, which numbers can be written on top of, may work better than default ship placement.)

Theme: Dominoes

Author/Opus: This is the 370th puzzle from our managing editor Serkan Yürekli.

Rules: Standard Battleship Sudoku rules. This combines Sudoku rules (insert a number from 1 to 9 into each cell so that no number repeats in any row, column, or bold region) with Battleship rules: Locate the given fleet, as in a Battleships puzzle. Each ship segment is numbered and these numbers must fit into a valid sudoku solution as well. Ships can be rotated when positioned in the grid, but different ships cannot be placed in adjacent cells that share an edge or corner. The clues outside the grid indicate the number of ship segments in that row/column. Numbers inside the grid at the start should be treated like “seas” and cannot belong to ships in the fleet.

Difficulty: 5 stars

Time Standards (highlight to view): Grandmaster = 20:00, Master = 55:00, Expert = 1:50:00

Solution: PDF and solving video.

Note: Follow this link for classic Battleships and this link for Battleships variations. If you are new to this puzzle type, here are our easiest Battleships to get started on. More Battleships puzzles can be found in Battleships and Variations, in The Art of Puzzles, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between number placement, ship placement, and shading modes. The shading mode in gray, which numbers can be written on top of, may work better than default ship placement.)

This is a “Twisted Tuesday” puzzle variation.

Theme: No Radar!

Rules: Standard Battleship Sudoku rules. However, there is no radar (no outside battleships clues).

Answer String: Enter the 5th row from left to right, followed by a comma, followed by the 5th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 1:45, Master = 2:30, Expert = 5:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between number placement, ship placement, and shading modes. The shading mode in gray, which numbers can be written on top of, may work better than default ship placement.)

Theme: Twister

Rules: Standard Battleship Sudoku rules.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 8th row from left to right.

Time Standard: Battleship Sudoku Grandmaster = 6:30, Master = 10:30, Expert = 21:00

Solution: PDF

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between number placement, ship placement, and shading modes. The shading mode in gray, which numbers can be written on top of, may work better than default ship placement.)

Theme: Four Islands

Rules: Standard Battleship Sudoku rules.

Answer String: Enter the 8th row from left to right, followed by a comma, followed by the 6th column from top to bottom.

Time Standard: Battleship Sudoku Grandmaster = 5:30, Master = 8:00, Expert = 16:00

Solution: PDF

Note: Advice on solving this puzzle has now been posted in “Ask Dr. Sudoku #8“

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between number placement, ship placement, and shading modes. The shading mode in gray, which numbers can be written on top of, may work better than default ship placement.)

Theme: Even Steven; the fleet has only certain kinds of numbers.

Rules: Standard Battleship Sudoku rules.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 6th column from top to bottom.

Time Standard: Battleship Sudoku Grandmaster = 1:30, Master = 2:15, Expert = 4:30

Solution: PDF