     Sudoku Solution Path   Puzzle Copyright © Kevin Stone R2C9 is the only square in row 2 that can be <8> R1C5 is the only square in row 1 that can be <8> R1C1 is the only square in row 1 that can be <9> R2C1 can only be <3> R2C3 can only be <5> R1C2 can only be <6> R3C2 can only be <2> R2C4 is the only square in row 2 that can be <9> R3C8 is the only square in row 3 that can be <5> R4C5 is the only square in row 4 that can be <1> R5C3 is the only square in row 5 that can be <8> R6C3 can only be <2> R5C6 is the only square in row 5 that can be <2> R6C8 is the only square in row 6 that can be <8> R7C8 is the only square in row 7 that can be <2> R7C5 is the only square in row 7 that can be <9> R8C4 is the only square in row 8 that can be <1> R8C1 is the only square in row 8 that can be <2> R5C4 is the only square in column 4 that can be <7> R2C6 is the only square in column 6 that can be <7> R2C7 can only be <4> Squares R5C5 and R6C5 in column 5 form a simple locked pair. These 2 squares both contain the 2 possibilities <45>. Since each of the squares must contain one of the possibilities, they can be eliminated from the other squares in the column.    R3C5 - removing <4> from <346> leaving <36>    R9C5 - removing <45> from <3456> leaving <36> Intersection of row 5 with block 6. The value <3> only appears in one or more of squares R5C7, R5C8 and R5C9 of row 5. These squares are the ones that intersect with block 6. Thus, the other (non-intersecting) squares of block 6 cannot contain this value.    R4C7 - removing <3> from <367> leaving <67>    R4C8 - removing <3> from <347> leaving <47> Intersection of column 7 with block 6. The values <67> only appears in one or more of squares R4C7, R5C7 and R6C7 of column 7. These squares are the ones that intersect with block 6. Thus, the other (non-intersecting) squares of block 6 cannot contain these values.    R4C8 - removing <7> from <47> leaving <4> Squares R1C8, R1C9, R9C8 and R9C9 form a Type-1 Unique Rectangle on <37>.    R9C9 - removing <37> from <3457> leaving <45> R9C8 is the only square in row 9 that can be <7> R1C8 can only be <3> R1C9 can only be <7> Intersection of block 9 with row 8. The value <3> only appears in one or more of squares R8C7, R8C8 and R8C9 of block 9. These squares are the ones that intersect with row 8. Thus, the other (non-intersecting) squares of row 8 cannot contain this value.    R8C3 - removing <3> from <36> leaving <6> R4C3 can only be <3> R9C1 can only be <4> R9C9 can only be <5> R5C1 can only be <6> R9C2 can only be <3> R5C9 can only be <3> R8C7 can only be <3> R4C2 can only be <7> R5C7 can only be <5> R8C9 can only be <4> R8C6 can only be <5> R9C5 can only be <6> R7C2 can only be <5> R3C5 can only be <3> R3C4 can only be <4> R4C7 can only be <6> R6C2 can only be <4> R5C5 can only be <4> R6C7 can only be <7> R6C5 can only be <5> R7C6 can only be <4> R7C4 can only be <3> R3C6 can only be <6> [Puzzle Code = Sudoku-20200603-VeryHard-098298]    