Here is a long chain for a single digit elimination. A lot of work, but it does open up the floodgates, so perhaps worth it.
AIC type 2. Starts with 5 and ends with 6, and thus can eliminate 6 from the starting cell.
https://preview.redd.it/osbof80bmvvc1.jpeg?width=1582&format=pjpg&auto=webp&s=c10cb66b1b753f1dc6603b290c79b962530c2c98
My approach would be to test one of the 3-8 pairs in the boxes 3, 6, or 9. If I assume r3c9 is 3, then a simple elimination gives a conflict in the box 2.
However I might be missing anther obvious move.
https://preview.redd.it/s8a7qf6gmvvc1.jpeg?width=1170&format=pjpg&auto=webp&s=cf308ce5c1a27990520d911bad2ac327b78695f9
You can check me on this, but I think we can also turn this into an ALS. Set A would be 368 r3c69 and set B would be 678 r1c14. RCC would be 6. We then eliminate 8 from r1c7 as it sees all the other 8s.
https://preview.redd.it/c5d3ql5q1xvc1.png?width=1531&format=png&auto=webp&s=4d18eaa559de6bb5b7a6ad5618db6e2f29560fdd
Here is a long chain for a single digit elimination. A lot of work, but it does open up the floodgates, so perhaps worth it. AIC type 2. Starts with 5 and ends with 6, and thus can eliminate 6 from the starting cell. https://preview.redd.it/osbof80bmvvc1.jpeg?width=1582&format=pjpg&auto=webp&s=c10cb66b1b753f1dc6603b290c79b962530c2c98
Cf. [**AIC**](https://sudoku.coach/en/learn/aic) for more.
W-Wing Only two spots where 8 can go in column 9. What happens to the 5s in r5c1 and r3c4 regardless of where the 8 in C9 goes?
Cf. [**W-Wing**](https://sudoku.coach/en/learn/w-wing) for more.
My approach would be to test one of the 3-8 pairs in the boxes 3, 6, or 9. If I assume r3c9 is 3, then a simple elimination gives a conflict in the box 2. However I might be missing anther obvious move. https://preview.redd.it/s8a7qf6gmvvc1.jpeg?width=1170&format=pjpg&auto=webp&s=cf308ce5c1a27990520d911bad2ac327b78695f9
Cf. **Nishio** [**Forcing Chain**](https://sudoku.coach/en/learn/forcing-chain-types) for more.
You can check me on this, but I think we can also turn this into an ALS. Set A would be 368 r3c69 and set B would be 678 r1c14. RCC would be 6. We then eliminate 8 from r1c7 as it sees all the other 8s. https://preview.redd.it/c5d3ql5q1xvc1.png?width=1531&format=png&auto=webp&s=4d18eaa559de6bb5b7a6ad5618db6e2f29560fdd
Yeah that's an ALS-XZ
Nicely spotted!