Last candidate 3 in C5 changed to solution Last candidate 1 in E2 changed to solution Last candidate 9 in E4 changed to solution Last candidate 6 in E5 changed to solution Last candidate 5 in E6 changed to solution Last candidate 4 in E8 changed to solution Last candidate 7 in F2 changed to solution Last candidate 3 in F4 changed to solution Last candidate 9 in B5 changed to solution Last candidate 2 in D2 changed to solution Last candidate 8 in D6 changed to solution

5 in F8 is last in row/box
6 in A3 is last in column
6 in J6 is last in column/box
8 in A4 is last in row/box

1 in C4 is last in column/box
3 in G6 is last in column/box

Naked Pair 6/9 on cells {D1|F1} means
- 9 can be removed from G1
- 9 can be removed from J1

Uniqueness Type 1 removing 6/9 at D9 because of D1,F1,F9
Last candidate 1 in D9 changed to solution

length=6. This XY-Chain is continuous and one value in each cell must be the solution, so all off-chain candidates can be removed
-2[C1]+5[C1]-5[C7]+6[C7]-6[H7]+4[H7]-4[H5]+8[H5]-8[G5]+4[G5]-4[G1]+2[G1]-2[C1]
- 4 can be removed from H1
- 4 can be removed from H2
- 4 can be removed from G9
- 2 can be removed from A1
- 2 can be removed from H1
- 2 can be removed from J1

length=4, chain ends: H4 and G1
This proves 2 is the solution at one or possibly both ends of the chain
-2[H4]+7[H4]-7[H1]+1[H1]-1[A1]+4[A1]-4[G1]+2[G1]
- 2 can be removed from H3

length=6, chain ends: F9 and J7
This proves 9 is the solution at one or possibly both ends of the chain
-9[F9]+6[F9]-6[C9]+2[C9]-2[C1]+5[C1]-5[C7]+6[C7]-6[H7]+4[H7]-4[J7]+9[J7]
- 9 can be removed from G9
- 9 can be removed from J9

9 in G3 is last in row

(Col->Row) 2 taken off A9, based on CG19
(Col->Row) 2 taken off B9, based on CG19
(Col->Row) 2 taken off J9, based on CG19

length=4, chain ends: A1 and H3
This proves 1 is the solution at one or possibly both ends of the chain
-1[A1]+4[A1]-4[G1]+2[G1]-2[J3]+3[J3]-3[H3]+1[H3]
- 1 can be removed from B3
- 1 can be removed from H1
Last candidate 7 in H1 changed to solution Last candidate 2 in H4 changed to solution Last candidate 7 in J4 changed to solution

1 in A1 is last in column/box
1 in B8 is last in row
1 in H3 is last in row/column/box

Pair: between Box 1 and Col 2:
- 4 can be removed from J2

length=4, chain ends: B9 and J1
This proves 4 is the solution at one or possibly both ends of the chain
-4[B9]+3[B9]-3[B3]+2[B3]-2[C1]+5[C1]-5[J1]+4[J1]
- 4 can be removed from J9

Pair: between Box 9 and Col 7:
- 4 can be removed from A7
- 4 can be removed from B7

Y-Wing pattern. Hinge: J9 (3/8), wings G9 J3, therefore
- 2 can be removed from G1
- 2 can be removed from J8
Last candidate 4 in G1 changed to solution Last candidate 8 in G5 changed to solution Last candidate 2 in G9 changed to solution Last candidate 4 in H5 changed to solution Last candidate 6 in H7 changed to solution Last candidate 3 in H8 changed to solution Last candidate 5 in J1 changed to solution Last candidate 9 in J8 changed to solution Last candidate 8 in J9 changed to solution

Last candidate 2 in A8 changed to solution Last candidate 2 in C1 changed to solution Last candidate 5 in C7 changed to solution Last candidate 6 in C9 changed to solution Last candidate 6 in D8 changed to solution Last candidate 9 in F9 changed to solution Last candidate 8 in H2 changed to solution Last candidate 3 in J2 changed to solution Last candidate 2 in J3 changed to solution Last candidate 4 in J7 changed to solution Last candidate 4 in A2 changed to solution Last candidate 7 in A6 changed to solution Last candidate 9 in A7 changed to solution Last candidate 3 in A9 changed to solution Last candidate 5 in B2 changed to solution Last candidate 3 in B3 changed to solution Last candidate 2 in B6 changed to solution Last candidate 7 in B7 changed to solution Last candidate 4 in B9 changed to solution Last candidate 9 in D1 changed to solution Last candidate 6 in F1 changed to solution