Step-by-Step Solution

for Tuesday 2nd December Fiendish

Number 6 is the only value possible in cell (1,5).

Single Candidate

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

Single Candidate

Number 3 is the only value possible in cell (1,7).

Single Candidate

Number 5 is the only value possible in cell (1,3).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

For column 8, Number 1 is only possible in cell (8,7)

Single Position

For row 1, number 8 is only possible in cell (3,1)

Single Position

For row 6, number 8 is only possible in cell (5,6)

Single Position

For column 6, Number 8 is only possible in cell (6,8)

Single Position

For column 6, Number 7 is only possible in cell (6,2)

Single Position

For column 3, Number 4 is only possible in cell (3,3)

Single Position

For box 8, candidates for 6 are all in column 5, so you can remove candidates from other blocks.

Candidate Lines

For row 1, number 6 is only possible in cell (6,1)

Single Position

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

Single Candidate

For row 1, number 9 is only possible in cell (8,1)

Single Position

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

Multiple Lines

Naked Pair for 4 and 5, can remove these as candidates from other cells.

Naked Pairs

Hidden Pair for 6 and 7, can remove other candidates from these cells.

Hidden Pairs

For column 5, Number 9 is only possible in cell (5,4)

Single Position

Number 3 is the only value possible in cell (2,4).

Single Candidate

Number 2 is the only value possible in cell (3,4).

Single Candidate

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

Single Candidate

Number 2 is the only value possible in cell (4,6).

Single Candidate

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

Single Candidate

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

Single Candidate

Number 9 is the only value possible in cell (2,7).

Single Candidate

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

Single Candidate

Number 3 is the only value possible in cell (4,1).

Single Candidate

Number 4 is the only value possible in cell (5,1).

Single Candidate

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

Single Candidate

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

Single Candidate

Number 5 is the only value possible in cell (7,4).

Single Candidate

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

Single Candidate

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

Single Candidate

Number 4 is the only value possible in cell (9,5).

Single Candidate

Number 7 is the only value possible in cell (8,6).

Single Candidate

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

Single Candidate

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

Single Candidate

Number 8 is the only value possible in cell (9,2).

Single Candidate

Number 6 is the only value possible in cell (7,2).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

Number 6 is the only value possible in cell (2,3).

Single Candidate

Number 1 is the only value possible in cell (5,3).

Single Candidate

Number 3 is the only value possible in cell (7,6).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

Number 9 is the only value possible in cell (4,8).

Single Candidate

Number 7 is the only value possible in cell (5,8).

Single Candidate

Number 2 is the only value possible in cell (7,8).

Single Candidate

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

Single Candidate

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

Single Candidate

Number 3 is the only value possible in cell (5,9).

Single Candidate

Number 5 is the only value possible in cell (6,9).

Single Candidate

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

Single Candidate