If lines are drawn along the rows and columns, connecting the squares involved, they can form two rectangles, connected at the corners. Solving these puzzles is a different matter entirely, since these are the most difficult puzzles we create. Difficulty depends on the type of steps required to solve them, and also on the number of each type of step. See our guide to solution rules for hard sudoku puzzles. First a couple of preliminary points: if you have ever completed any Fiendish or Super Fiendish Sudoku, you will be familiar with noting down candidates or pencil marks. If you prefer to enter your own pencilmarks, up to six digits can be entered in each cell. You can add symbols too, such as question marks. If you really like Super Fiendish, you will have to wait a little longer for The Times Sudoku 7 with 25 extremely hard Sudoku, many requiring x-wing or swordfish to complete.

In this case, this particular number can be eliminated as a possibility for all other squares in those three columns. Sudoku evil is a 9×9 grid sudoku puzzle with the highest possible level of difficulty. It’s an advanced level only for experienced sudoku solvers. Simple logic and basic knowledge of sudoku rules won’t cut it – you as a player should know advanced sudoku solving techniques and understand how to apply them in practice. If you like playing some seriously hard Sudoku, try the puzzles at the end of The Times Sudoku 6 book with some requiring the swordfish technique.

Solutions

The pivot contains candidates XY. The pincers - candidates XZ and YZ. Any cell that intersects both pincers can’t longer contain a candidate for digit Z, because the pivot means either of the pincers to contain this digit. Why play Evil Sudoku? In general, an x-wing is found when for two rows, there are two, and only two, possible squares in which a particular number can be placed, and for both rows these squares lie in the same two columns. In this case, this particular number can be eliminated as a possibility for all other squares in those two columns.

This is a moredifficult method, one of the most complicated for any Sudoku you will find in print.From today onwards, you will find the swordfish technique become a regular feature in the Times2 .The swordfish is similar to the x-wing technique, but on a larger scale, with three rows and columns instead of two. submissions and try for the Experts list. Anyone can get into the Top Sudoku Expert list - this is now the sum of all your correct entries for the So, as we increase the difficulty Super Fiendish, the time has come to present the essential techniques for solving the most difficult Sudoku puzzles. Using the same logic in the last column, you can also eliminate the 7 as a possibility from all squares which are not in either highlighted row (Fig. 2). In Fig. 4, the relevant pencil marks are entered to show that you have two possible squares in which the 3 can be placed in the third and fourth columns, and three possible squares in the seventh column (highlighted).Playing sudoku evil online has a lot of advantages. While solving sudoku, your brain exercises logic, learns to make decisions, and puts your memory to the test. Regularly playing evil sudoku is a good method of improving your concentration. Play 1 or 2 evil sudoku games every day and you will not have any problems with losing focus while doing important things. It is a fact that you cannot place the 7 in the first column square of both the highlighted rows at the same time.

Therefore, on each of the three intersecting rows, the 3 must be placed in one of the highlighted columns. So, you can eliminate the 3 pencil mark from all other unsolved squares in these intersecting rows (Fig.Pencil marks are small numbers, usually written at the top of each unsolved square, listing all the possible values for that square. Fig. 3 is a partially solved Sudoku, using easy and medium difficulty solving techniques; no more squares can be solved using them. XY-Wing strategy is an advanced technique for eliminating candidates. Let’s review it with an example. Let’s say, there are 3 different cells with exactly 2 candidates (notes) each that are related to each other. The cell in the center is called the pivot. The two others are called the pincers. Each of these cells can include only one of 3 digits, named X, Y, Z. It means that any 3 digits can replace these letters.

Even though evil sudoku is an extremely difficult game level, many experienced players find it the best way for brain training and developing mental skills. How to solve Sudoku Evil? Extreme Sudoku posts five new puzzles every day. Each puzzle has a unique solution and can be solved with pure logic. Lots of it. Guessing is never required - but it may help! Here we present the techniques that will help you solve the hardest puzzles using only logic and no guesswork. A swordfish is found when for three rows, there are two or three possible squares in which a particular number can be placed, and for all three rows these squares lie in the same three columns.

Extreme Sudoku

InNovember 2006, The Times introduced a new extreme level of Sudoku giving players a moredifficult level of logic: Super Fiendish. While it's totally fine to play sudoku intuitively on the easy levels, evil sudoku requires the knowledge of some strategies. Here is the most popular one for solving sudoku on the evil level. The basic rules of Sudoku are easy. Just place the digits from 1 to 9 in each empty cell. Each row, column, and 3 x 3 box must contain only one of each of the 9 digits.