Step-by-Step Solution

for Thursday 1st January Diabolical

For box 1, Number 4 is only possible in cell (2,3)

Single Position

For row 7, number 7 is only possible in cell (1,7)

Single Position

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

Single Position

For column 2, Number 5 is only possible in cell (2,8)

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

Candidate Lines

Hidden Pair for 4 and 9, can remove other candidates from these cells.

Hidden Pairs

For box 4, candidates for 1 are all in column 3, so you can remove candidates from other blocks.

Candidate Lines

Naked Triple for 3, 5 and 7, can remove these as candidates from other cells.

Naked Triples

Candidates for 5 in boxes 1 and 3 force the candidates in box 2 to be in the remaining line.

Multiple Lines

Hidden Pair for 5 and 7, can remove other candidates from these cells.

Hidden Pairs

For row 1, number 3 is only possible in cell (4,1)

Single Position

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

Single Candidate

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

Single Candidate

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

Single Position

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

Single Position

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

Single Candidate

For row 9, number 6 is only possible in cell (1,9)

Single Position

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

Single Candidate

Number 1 is the only value possible in cell (5,2).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

Number 8 is the only value possible in cell (3,5).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

Number 2 is the only value possible in cell (3,8).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

For row 4, number 8 is only possible in cell (9,4)

Single Position

For row 2, number 2 is only possible in cell (9,2)

Single Position

For row 5, number 6 is only possible in cell (7,5)

Single Position

For column 9, Number 3 is only possible in cell (9,8)

Single Position

For row 3, number 1 is only possible in cell (9,3)

Single Position

For row 6, number 1 is only possible in cell (8,6)

Single Position

For row 6, number 3 is only possible in cell (7,6)

Single Position

Number 5 is the only value possible in cell (7,2).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

Number 3 is the only value possible in cell (8,2).

Single Candidate

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

Single Candidate

Number 9 is the only value possible in cell (7,3).

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

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

Single Candidate

Number 4 is the only value possible in cell (5,6).

Single Candidate

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

Single Candidate

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

Single Candidate