Step-by-Step Solution

for Monday 22nd December Fiendish

Number 6 is the only value possible in cell (2,5).

Single Candidate

Number 4 is the only value possible in cell (1,7).

Single Candidate

Number 3 is the only value possible in cell (3,7).

Single Candidate

Number 5 is the only value possible in cell (2,8).

Single Candidate

Number 3 is the only value possible in cell (2,1).

Single Candidate

For column 9, Number 6 is only possible in cell (9,4)

Single Position

For row 2, number 5 is only possible in cell (1,2)

Single Position

For row 6, number 5 is only possible in cell (6,6)

Single Position

For box 7, candidates for 9 are all in row 9, so you can remove candidates from other blocks.

Candidate Lines

For box 8, candidates for 7 are all in column 6, so you can remove candidates from other blocks.

Candidate Lines

For box 6, candidates for 1 are all in column 7, so you can remove candidates from other blocks.

Candidate Lines

For box 7, candidates for 6 are all in row 9, so you can remove candidates from other blocks.

Candidate Lines

For column 6, Number 6 is only possible in cell (6,1)

Single Position

For box 2, candidates for 9 are all in column 4, so you can remove candidates from other blocks.

Candidate Lines

Candidates for 7 in boxes 4 and 5 force the candidates in box 6 to be in the remaining line.

Multiple Lines

Naked Pair for 2 and 3, can remove these as candidates from other cells.

Naked Pairs

For box 2, candidates for 3 are all in row 2, so you can remove candidates from other blocks.

Candidate Lines

Candidates for 2 in boxes 1 and 2 force the candidates in box 3 to be in the remaining line.

Multiple Lines

Number 8 is the only value possible in cell (8,2).

Single Candidate

For row 8, number 8 is only possible in cell (7,8)

Single Position

For row 8, number 9 is only possible in cell (8,8)

Single Position

For row 5, number 9 is only possible in cell (6,5)

Single Position

Number 4 is the only value possible in cell (6,4).

Single Candidate

Number 1 is the only value possible in cell (2,4).

Single Candidate

Number 4 is the only value possible in cell (2,2).

Single Candidate

Number 2 is the only value possible in cell (3,2).

Single Candidate

Number 3 is the only value possible in cell (5,2).

Single Candidate

Number 1 is the only value possible in cell (6,2).

Single Candidate

Number 9 is the only value possible in cell (4,3).

Single Candidate

Number 2 is the only value possible in cell (4,1).

Single Candidate

Number 6 is the only value possible in cell (3,3).

Single Candidate

Number 1 is the only value possible in cell (1,3).

Single Candidate

Number 8 is the only value possible in cell (4,4).

Single Candidate

Number 7 is the only value possible in cell (3,4).

Single Candidate

Number 2 is the only value possible in cell (5,4).

Single Candidate

Number 9 is the only value possible in cell (7,4).

Single Candidate

Number 3 is the only value possible in cell (4,5).

Single Candidate

Number 2 is the only value possible in cell (1,6).

Single Candidate

Number 8 is the only value possible in cell (1,5).

Single Candidate

Number 9 is the only value possible in cell (1,1).

Single Candidate

Number 8 is the only value possible in cell (3,1).

Single Candidate

Number 4 is the only value possible in cell (3,6).

Single Candidate

Number 6 is the only value possible in cell (4,6).

Single Candidate

Number 7 is the only value possible in cell (5,6).

Single Candidate

Number 3 is the only value possible in cell (8,6).

Single Candidate

Number 1 is the only value possible in cell (7,6).

Single Candidate

Number 7 is the only value possible in cell (6,7).

Single Candidate

Number 2 is the only value possible in cell (7,7).

Single Candidate

Number 3 is the only value possible in cell (7,3).

Single Candidate

Number 2 is the only value possible in cell (9,3).

Single Candidate

Number 7 is the only value possible in cell (9,5).

Single Candidate

Number 5 is the only value possible in cell (9,1).

Single Candidate

Number 7 is the only value possible in cell (7,1).

Single Candidate

Number 2 is the only value possible in cell (8,5).

Single Candidate

Number 1 is the only value possible in cell (9,7).

Single Candidate

Number 4 is the only value possible in cell (4,8).

Single Candidate

Number 6 is the only value possible in cell (5,8).

Single Candidate

Number 3 is the only value possible in cell (9,8).

Single Candidate

Number 6 is the only value possible in cell (1,9).

Single Candidate

Number 9 is the only value possible in cell (3,9).

Single Candidate

Number 1 is the only value possible in cell (4,9).

Single Candidate

Number 3 is the only value possible in cell (6,9).

Single Candidate

Number 5 is the only value possible in cell (7,9).

Single Candidate

Number 7 is the only value possible in cell (8,9).

Single Candidate

Number 4 is the only value possible in cell (9,9).

Single Candidate