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Sudoku Xtra, written by Dr Gareth Moore
Sudoku Xtra 24
logic puzzle compendium
Printed puzzles from Dr Gareth Moore

Killer Sudoku

Jigsaw Sudoku
Consecutive Sudoku
Kropki Sudoku
Sudoku XV
Oddpair Sudoku
Toroidal Sudoku
Killer Sudoku-X
Killer Sudoku

Jigsaw Killer

Looking for puzzles for your book, magazine or newspaper?


Killer Sudoku-X puzzles and instructions

Play free Killer Sudoku-X puzzles:
Killer X   16th Mar
  Killer Sudoku-X 492 
Killer X   2nd Mar
  Killer Sudoku-X 490 
Killer X   12th Feb
  Killer Sudoku-X 489 
Killer X   30th Jan
  Killer Sudoku-X-6 84 
Killer Sudoku-X puzzles include all the rules of regular Sudoku-X but add in dashed-line 'cages' which must sum to given values. Killer Sudoku-X is also sometimes known as Sumdoku-X, Mathdoku-X or Addoku-X.

How to solve Killer Sudoku-X puzzles
Killer Sudoku-X adds both diagonal "X" regions and also additional "Killer" regions to a regular Sudoku. Taking the "X" part first, while in a regular Sudoku puzzle you must place each of the numbers 1 to 9 (or 1 to the size of the puzzle) into each of the rows, columns and bold-lined boxes, Sudoku-X extends this with two new diagonal regions which must also contain one of each number. These are marked on the grid so you don't forget them.

Taking the "Killer" part next, Killer Sudoku adds dashed-line cages which must contain numbers that add up to a given total - and no digit can repeat in any dashed-line cage.

So Killer Sudoku-X combines the Sudoku-X and Killer Sudoku variants of Sudoku into a single puzzle.

Killer Sudoku-X exampleLook at the solved Killer Sudoku-X puzzle on the left. In this 6x6 puzzle notice how each of the marked diagonals contains one each of 1 to 6. Also consider the '7' cage in the top-middle of the puzzle. The values in it are 5 and 2, which add up to the given clue, 7.

Remember that you cannot repeat a number within a cage. This means that the solution to the 7 cage on the right-hand side of the puzzle must be 1+2+4 in some order, since any other solution over three squares would repeat a number. For example 2+2+3 would be invalid.

Every Killer Sudoku-X puzzle only ever has one possible solution, and it can always be reached via reasonable logical deduction. In other words, guessing is never required.

Killer Sudoku-X puzzles on puzzlemix appear at a wide range of sizes and difficulties. Usually they are 6x6, 8x8 or 9x9. In each respective case you must place 1-6, 1-8 or 1-9 once each into every row, column, bold-lined rectangle and marked diagonal.

Other types of puzzle
It's not just Killer Sudoku-X you can solve online at puzzlemix. You can also solve logic puzzles that include these:
CalcudokuConsecutive SudokuFutoshikiHanjie
HitoriJigsaw SudokuKakuroKiller Jigsaw Sudoku
Killer SudokuKiller Sudoku ProKropki SudokuNurikabe
Odd Pair SudokuSkyscraperSlitherlinkSudoku
Sudoku XVSudoku-XToroidal Sudoku

Are you searching for help with Killer Sudoku-X puzzles? Stuck on solving Mathdoku-X? Don't know the instructions for Sumdoku-X? Need Adddoku-X instructions? Want solving hints and tips for Killer Sudoku-X? Then puzzlemix is the place for you to play Killer Sudoku-X puzzles online.

External links

Looking for printed Killer Sudoku-X puzzles? Visit Sudoku Xtra for puzzle magazines and books.

Or are you looking for a Killer Sudoku-X puzzle supplier? If so then check out Any Puzzle Media, my puzzle production company.

All site contents ©Gareth Moore 2005-2017 - email - publishers please visit Any Puzzle Media