We do not want to scare you away from Sudoku, but it is true – in 2006 the World’s Hardest Sudoku was discovered, codenamed: AI Escargot with even computer programs having to recurse (iteratively probing and probing) through multiple levels before finding a solution.

Al Escargot - 2006 World's Hardest Sudoku Puzzle

The man behind this 2006 discovery is none other than Arto Inkala, a Finnish mathematician. Four years later, he is back – and this time around he has outdone himself by developing an even harder Sudoku puzzle than the previous one he developed.

World's Hardest Sudoku Puzzle by Arto Inkala - 2010

Arto Inkala on his new discovery: “It will test your brain power to the maximum and, I hope, rival AI Escargot. Good luck.”

Al Escargot – 2006 World’s Hardest Sudoku Puzzle

World’s Hardest Sudoku Puzzle by Arto Inkala – 2010

If you plan on testing your brain power to the maximum, do keep us posted by telling us on your attempts in our comment section. Good Luck!