A Medium 7×7 Puzzle Solved with Shape Squeeze in 13 Steps

This 7×7 board rates as medium (difficulty score 793). Solving it from scratch takes 13 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 2, 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 1, so its marker has to land there; that clears every other open cell in the row.
3. Then, every open cell left in this region sits in row 3, so its marker has to land there; that clears every other open cell in the row.
4. After that, every open cell left in this region sits in row 4, so its marker has to land there; that clears every other open cell in the row.
5. Now, every remaining candidate in this region touches B2, so whichever candidate ends up marked will clear it, and it can be ruled out now regardless of which one wins.
6. From there, place a marker at A2. Region has exactly one open cell left. Placing here clears the rest of row 2, column A, and its region. Placing here also clears its 1 touching neighbour.
7. Following that, place a marker at C1. Region has exactly one open cell left. Placing here clears the rest of row 1, column C, and its region.
8. First, 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. Placing here also clears its 1 touching neighbour.
9. Next, place a marker at E7. Region has exactly one open cell left. Placing here clears the rest of row 7, column E, and its region. Placing here also clears its 1 touching neighbour.
10. Then, every remaining candidate in this region touches F5 and G5, so whichever candidate ends up marked will clear them, and they can be ruled out now regardless of which one wins.
11. After that, place a marker at G6. Region has exactly one open cell left. Placing here clears the rest of row 6, column G, and its region.
12. Now, place a marker at F4. Region has exactly one open cell left.
13. Finally, place a marker at B5. Region has exactly one open cell left.

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