A Medium 11×11 Puzzle Solved with Shape Squeeze in 16 Steps

This 11×11 board rates as medium (difficulty score 797). Solving it from scratch takes 16 logical steps, using 5 techniques: Single cell, Row/column exclusion, Adjacency clear, Region confinement, Shape squeeze. Every step below is forced: nothing here is a guess.

1. First, every open cell left in this region sits in row 11, so its marker has to land there; that clears every other open cell in the row.
2. Next, every open cell left in this region sits in row 10, so its marker has to land there; that clears every other open cell in the row.
3. Then, every remaining candidate in this region touches B7, so whichever candidate ends up marked will clear it, and it can be ruled out now regardless of which one wins.
4. After that, every remaining candidate in this region touches C9 and D9 and D11, so whichever candidate ends up marked will clear them, and they can be ruled out now regardless of which one wins.
5. Now, place a marker at E11. Region has exactly one open cell left. Placing here clears the rest of row 11, column E, and its region. Placing here also clears its 1 touching neighbour.
6. From there, place a marker at C10. Region has exactly one open cell left. Placing here clears the rest of row 10, column C, and its region. Placing here also clears its 1 touching neighbour.
7. Following that, place a marker at B6. Region has exactly one open cell left. Placing here clears the rest of row 6, column B, and its region. Placing here also clears its 2 touching neighbours.
8. First, every open cell left in this region sits in column A, so its marker has to land there; that clears every other open cell in the column.
9. Next, place a marker at D3. Region has exactly one open cell left. Placing here clears the rest of row 3, column D, and its region.
10. Then, place a marker at F7. Region has exactly one open cell left. Placing here clears the rest of row 7, column F, and its region. Placing here also clears its 1 touching neighbour.
11. After that, place a marker at G9. Region has exactly one open cell left. Placing here clears the rest of row 9, column G, and its region. Placing here also clears its 1 touching neighbour.
12. Now, place a marker at A8. Region has exactly one open cell left. Placing here clears the rest of row 8, column A, and its region.
13. From there, place a marker at H5. Region has exactly one open cell left. Placing here clears the rest of row 5, column H, and its region. Placing here also clears its 1 touching neighbour.
14. Following that, place a marker at I2. Region has exactly one open cell left. Placing here clears the rest of row 2, column I, and its region. Placing here also clears its 1 touching neighbour.
15. First, place a marker at J4. Region has exactly one open cell left. Placing here clears the rest of row 4, column J, and its region.
16. Finally, place a marker at K1. Region has exactly one open cell left.

The key move here was Shape squeeze. Once you can spot that, this board falls quickly. ∎