Greater Than Killer Sudoku: Another extremely hard puzzle
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25:26
Very Tough Killer Sudoku: By Request!
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31:15
Viewer-requested Extreme Killer Sudoku - Not For The Faint-Hearted
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23:21
The World's Hardest Killer Sudoku?
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29:27
Extreme Sudoku: Viewer-Requested Solve Of A Brutal Puzzle
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47:15
How Many Rinky-Dinks Will Solve This Puzzle?!
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24:51
¿SABES HALLAR EL ÁREA DEL CÍRCULO SOMBREADO EN ROJO? Geometría Básica
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29:31
[Hard] World-Class Killer Sudoku
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9:40