Who is hard Killer Sudoku for?

Killer Sudoku is a fun number puzzle in the family of Sudoku puzzles. There’s a common opinion that even though its name contains the word “killer”, it is actually easier than the classic sudoku. Well, not if you play a hard Killer Sudoku.

Hard Killer Sudoku levels have the same rules as any other level, the only difference is very few numbers on the grid from the beginning. This makes the game pretty hardcore and requires longer playing time to fill out all the numbers. It’s definitely a great fit for players who have had enough of the classic sudoku and want to step up their game.

“Minimum and Maximum” strategy

A useful technique to master hard killer Sudoku levels is trying to predict the numbers in a cage. No need for a crystal ball here, it’s not as hard as it seems. If you have a cage with the value of 3, you know for sure that it’s only 1 and 2 that can be inside. The same goes for 4 as a sum of 3+1 (2+2 breaks the rule of not repeating the numbers).

Here are a few more such examples of two-cell cages:

6 (3 cells) = {1,2,3}
7 (3 cells) = {1,2,4}
16 (2 cells) = {7,9}
17 (2 cells) = {8,9}

After breaking down the cage value into numbers, don’t forget to use notes to remember them. When you have enough notes on the grid, you’ll be able to make exclusions,  the overall picture becomes clearer and you’ll master the game in a snap!

Why you should play Killer Sudoku

While easy/medium Killer Sudoku is like jogging in terms of sports, hard Killer Sudoku is a real harcore workout for your brain. Try playing it regularly and soon you’ll be ready to take on the final boss in the world of number puzzles – Expert Killer Sudoku.