Last candidate 8 in G8 changed to solution

7 in H9 is last in row/column/box

Pair: between Box 5 and Col 5:
- 1 can be removed from A5
- 1 can be removed from B5
- 1 can be removed from G5
- 1 can be removed from H5
- 1 can be removed from J5

Pair: between Box 3 and Row B:
- 2 can be removed from B4
- 2 can be removed from B5
- 2 can be removed from B6

Naked Triple 4/6/8 on cells {A3|H3|J3} means
- 4/8 can be removed from B3
- 4/6/8 can be removed from E3
- 4 can be removed from F3
- 6 can be removed from H2

(Col->Row) 7 taken off B1, based on CD15
(Col->Row) 7 taken off E1, based on CD15
(Col->Row) 7 taken off B5, based on CD15
(Col->Row) 7 taken off E5, based on CD15

If +1[G6] then -1[A6] forcing +1[A7] which removes all 1s from Box 9, so G6 cannot be 1

If +8[H5] then -8[A5] forcing +8[A3] which removes all 8s from Box 7, so H5 cannot be 8

If +9[H5] then -9[A5] forcing +9[A7] which removes all 9s from Box 9, so H5 cannot be 9

Naked Quad 2/3/5/7 on cells {E3|E4|E5|E6} means
- 3 can be removed from E1
- 5 can be removed from E2
- 2/3 can be removed from E7
- 5 can be removed from E9
- 2 can be removed from F5

2 in B7 is last in column
2 in F8 is last in row/box

Pair: between Box 6 and Row D:
- 3 can be removed from D1
- 3 can be removed from D5

If +5[D2] then -5[C2] forcing +5[C9] which removes all 5s from Box 6, so D2 cannot be 5

length=4. This XY-Chain is continuous and one value in each cell must be the solution, so all off-chain candidates can be removed
-4[A3]+8[A3]-8[J3]+6[J3]-6[J6]+1[J6]-1[A6]+4[A6]
- 8 can be removed from H3
- 6 can be removed from J5
- 6 can be removed from J7
- 1 can be removed from B6
- 1 can be removed from H6
- 4 can be removed from A5
- 4 can be removed from A7

4 in E7 is last in column

Pair: between Box 6 and Col 9:
- 9 can be removed from B9
- 9 can be removed from C9

XYZ-Wing pattern. Hinge: J7 (1/3/9), wings A7 H8, therefore
- 9 can be removed from H7

length=4, chain ends: A6 and C9
This proves 4 is the solution at one or possibly both ends of the chain
-4[A6]+1[A6]-1[A7]+9[A7]-9[B8]+5[B8]-5[C9]+4[C9]
- 4 can be removed from C5

(RULE 4): Uncoloured candidate 6 in H5 can see two different coloured candidates of 6 elsewhere.
(RULE 4): Uncoloured candidate 6 in H6 can see two different coloured candidates of 6 elsewhere.

(RULE 5): Uncoloured candidate 4 in G1 can see coloured 4 elsewhere and an oppositely coloured 1 in its own cell. It can be removed.
(RULE 5): Uncoloured candidate 8 in B4 can see coloured 8 elsewhere and an oppositely coloured 1 in its own cell. It can be removed.

Triple: between Box 7 and Row H:
- 4 can be removed from H5
- 4 can be removed from H6

Hidden Pair 4/6 in Col 5, on cells {B5|G5}
- removes 8/9 from B5
- removes 2 from G5

8 in A5 is last in box

Last candidate 4 in A3 changed to solution

Last candidate 1 in A6 changed to solution
Last candidate 6 in H3 changed to solution

Last candidate 9 in A7 changed to solution
Last candidate 9 in B4 changed to solution
Last candidate 8 in J3 changed to solution
Last candidate 6 in J6 changed to solution

Last candidate 5 in B8 changed to solution
Last candidate 2 in C4 changed to solution
Last candidate 4 in G5 changed to solution

Last candidate 8 in B2 changed to solution
Last candidate 6 in B5 changed to solution
Last candidate 7 in C5 changed to solution
Last candidate 4 in C9 changed to solution
Last candidate 3 in D8 changed to solution
Last candidate 3 in E4 changed to solution
Last candidate 2 in G6 changed to solution

Last candidate 3 in B1 changed to solution
Last candidate 4 in B6 changed to solution
Last candidate 1 in B9 changed to solution
Last candidate 9 in C1 changed to solution
Last candidate 6 in D7 changed to solution
Last candidate 1 in G1 changed to solution
Last candidate 5 in H6 changed to solution
Last candidate 9 in H8 changed to solution
Last candidate 1 in J4 changed to solution

Last candidate 7 in B3 changed to solution
Last candidate 5 in C2 changed to solution
Last candidate 1 in D2 changed to solution
Last candidate 8 in E1 changed to solution
Last candidate 7 in E6 changed to solution
Last candidate 4 in F1 changed to solution
Last candidate 6 in G9 changed to solution
Last candidate 4 in H2 changed to solution
Last candidate 8 in H4 changed to solution
Last candidate 3 in H5 changed to solution
Last candidate 3 in J7 changed to solution

Last candidate 7 in D1 changed to solution
Last candidate 5 in D5 changed to solution
Last candidate 5 in E3 changed to solution
Last candidate 9 in E9 changed to solution
Last candidate 9 in F2 changed to solution
Last candidate 2 in H1 changed to solution
Last candidate 1 in H7 changed to solution
Last candidate 9 in J5 changed to solution

Last candidate 8 in D9 changed to solution
Last candidate 6 in E2 changed to solution
Last candidate 2 in E5 changed to solution
Last candidate 3 in F3 changed to solution
Last candidate 1 in F5 changed to solution
Last candidate 5 in F9 changed to solution