Re: Difficult Killer Sudoku 31/7

This puzzle is no longer worth points, so I can show my method.

I will refer to the 3x3 cell areas as a box, I don't know if there is a correct name for them, but I always think of them as a box.

Step 1.

Calculate cages f6 (22) and f8 (38); cage f6=5,6,7,8,9 & cage f8=3,5,6,7,8,9

Step 2.

In the lower right side box there are 6 cells with only 6 possible values, that means cells h7, i7 & i8 must be the other 3 values (1,2 & 4). Therefore h7 must be 2, because it can not be in the i7 cage.

Step 3.

Add the cages in the centre/right box (cells g4 to i6): (noting that cell h7 is solved) cage g4:16 + cage i5:8 = 24, this means the cells i4 + g5 + g6 = 21 (The cells coloured blue in the picture below).

Because i4 + g5 + g6 =21 the values in those cells must be at least 4, and the unsolved cells in cage g4(18) can not be 2 because cell h7 within that cage is 2. This means that the only remaining place for the value 2 in that box is the i5 cage, so that cage must be 2 & 6.

These 3 steps are shown in the 3 images below.

From this point it is all basic methods to complete the puzzle.

Step 1

Step 2

Step 3