Copyright © Kevin Stone

R2C2 can only be <6>

R1C5 is the only square in row 1 that can be <5>

R2C3 is the only square in row 2 that can be <3>

R4C6 is the only square in row 4 that can be <5>

R5C6 is the only square in row 5 that can be <6>

R6C4 is the only square in row 6 that can be <3>

R5C9 is the only square in row 5 that can be <3>

R6C5 is the only square in row 6 that can be <9>

R2C7 is the only square in row 2 that can be <9>

R3C4 is the only square in row 3 that can be <9>

R5C1 is the only square in row 5 that can be <9>

R5C2 is the only square in row 5 that can be <5>

R7C1 is the only square in row 7 that can be <5>

R8C3 is the only square in row 8 that can be <6>

R9C7 is the only square in row 9 that can be <5>

R9C9 is the only square in row 9 that can be <9>

Squares R4C3 and R6C3 in column 3 form a simple locked pair. These 2 squares both contain the 2 possibilities <47>. Since each of the squares must contain one of the possibilities, they can be eliminated from the other squares in the column.

R1C3 - removing <4> from <248> leaving <28>

R1C1 is the only square in row 1 that can be <4>

Intersection of row 1 with block 3. The value <1> only appears in one or more of squares R1C7, R1C8 and R1C9 of row 1. These squares are the ones that intersect with block 3. Thus, the other (non-intersecting) squares of block 3 cannot contain this value.

R3C8 - removing <1> from <12478> leaving <2478>

R3C9 - removing <1> from <127> leaving <27>

Intersection of column 8 with block 9. The value <1> only appears in one or more of squares R7C8, R8C8 and R9C8 of column 8. These squares are the ones that intersect with block 9. Thus, the other (non-intersecting) squares of block 9 cannot contain this value.

R7C9 - removing <1> from <127> leaving <27>

R8C7 - removing <1> from <1278> leaving <278>

R1C9 is the only square in column 9 that can be <1>

Intersection of block 7 with row 9. The value <2> only appears in one or more of squares R9C1, R9C2 and R9C3 of block 7. These squares are the ones that intersect with row 9. Thus, the other (non-intersecting) squares of row 9 cannot contain this value.

R9C5 - removing <2> from <128> leaving <18>

Squares R3C6 and R7C6 in column 6 and R3C9 and R7C9 in column 9 form a Simple X-Wing pattern on possibility <2>. All other instances of this possibility in rows 3 and 7 can be removed.

R3C1 - removing <2> from <12> leaving <1>

R7C4 - removing <2> from <248> leaving <48>

R3C8 - removing <2> from <2478> leaving <478>

R7C8 - removing <2> from <1278> leaving <178>

R3C2 can only be <8>

R9C1 can only be <2>

R1C3 can only be <2>

R9C3 can only be <8>

R9C5 can only be <1>

R1C7 can only be <8>

R4C7 is the only square in row 4 that can be <1>

R6C7 can only be <7>

R6C3 can only be <4>

R8C7 can only be <2>

R5C8 can only be <2>

R8C5 can only be <8>

R7C9 can only be <7>

R5C4 can only be <8>

R2C8 can only be <4>

R6C6 can only be <1>

R4C3 can only be <7>

R7C2 can only be <1>

R3C9 can only be <2>

R8C8 can only be <1>

R5C5 can only be <7>

R7C4 can only be <4>

R8C2 can only be <7>

R7C8 can only be <8>

R2C5 can only be <2>

R3C8 can only be <7>

R3C6 can only be <4>

R7C6 can only be <2>

R4C4 can only be <2>

R4C5 can only be <4>