Step-by-Step Solution

for Sunday 22nd December Fiendish

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

Single Candidate

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

Single Candidate

For box 9, Number 7 is only possible in cell (7,7)

Single Position

For column 9, Number 1 is only possible in cell (9,2)

Single Position

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

Single Candidate

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

Single Candidate

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

Single Candidate

For column 7, Number 4 is only possible in cell (7,9)

Single Position

For row 3, number 6 is only possible in cell (1,3)

Single Position

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

Single Position

For box 1, candidates for 9 are all in column 3, so you can remove candidates from other blocks.

Candidate Lines

For box 7, candidates for 8 are all in column 3, so you can remove candidates from other blocks.

Candidate Lines

For box 9, candidates for 8 are all in column 9, so you can remove candidates from other blocks.

Candidate Lines

Candidates for 9 in boxes 4 and 5 force the candidates in box 6 to be in the remaining line.

Multiple Lines

Naked Triple for 2, 5 and 9, can remove these as candidates from other cells.

Naked Triples

For box 7, Number 5 is only possible in cell (2,7)

Single Position

Number 4 is the only value possible in cell (6,7).

Single Candidate

Number 8 is the only value possible in cell (3,7).

Single Candidate

Number 6 is the only value possible in cell (9,7).

Single Candidate

Number 2 is the only value possible in cell (4,7).

Single Candidate

Number 7 is the only value possible in cell (4,8).

Single Candidate

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

Single Candidate

Number 2 is the only value possible in cell (1,8).

Single Candidate

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

Single Candidate

Number 8 is the only value possible in cell (4,1).

Single Candidate

Number 7 is the only value possible in cell (5,1).

Single Candidate

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

Single Candidate

Number 4 is the only value possible in cell (2,8).

Single Candidate

Number 1 is the only value possible in cell (3,9).

Single Candidate

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

Single Candidate

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

Single Candidate

For row 4, number 1 is only possible in cell (1,4)

Single Position

For row 9, number 6 is only possible in cell (4,9)

Single Position

For column 3, Number 5 is only possible in cell (3,6)

Single Position

For row 5, number 4 is only possible in cell (4,5)

Single Position

For row 4, number 7 is only possible in cell (8,4)

Single Position

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

Single Candidate

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

Single Candidate

Number 2 is the only value possible in cell (7,1).

Single Candidate

Number 9 is the only value possible in cell (3,1).

Single Candidate

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

Single Candidate

Number 8 is the only value possible in cell (7,3).

Single Candidate

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

Single Candidate

Number 7 is the only value possible in cell (1,5).

Single Candidate

Number 8 is the only value possible in cell (1,6).

Single Candidate

Number 3 is the only value possible in cell (5,6).

Single Candidate

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

Single Candidate

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

Single Candidate

Number 5 is the only value possible in cell (6,3).

Single Candidate

Number 8 is the only value possible in cell (5,4).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

Number 9 is the only value possible in cell (2,6).

Single Candidate

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

Single Candidate

Number 2 is the only value possible in cell (9,6).

Single Candidate

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

Single Candidate

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

Single Candidate