Medium Star Battle answer — July 23, 2025

Full written solution

Every deduction from the walkthrough above, in order. Each technique is explained in the Star Battle strategy guide.

1. Starting position — the grid is split into regions (bold outlines). Each row, column, and region needs exactly two stars, and no two stars may touch.
2. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 5, column 3).
3. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 6, column 7).
4. Three candidates with two adjacent: Isolated candidate must hold a star (row 5, column 7).
5. Mark 7 cells adjacent to stars as X (row 4, column 6).
6. Two-option rule: Cell adjacent to both candidates (row 8, column 7).
7. Two-option rule: Cell adjacent to both candidates (row 8, column 8).
8. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 1, column 2).
9. Three candidates with two adjacent: Isolated candidate must hold a star (row 2, column 3).
10. Mark 7 cells adjacent to stars as X (row 1, column 3).
11. Region completion: 1 star needed, 1 candidate (row 1, column 1).
12. Mark 1 cell adjacent to stars as X (row 2, column 1).
13. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 8, column 5).
14. Three candidates with two adjacent: Isolated candidate must hold a star (row 8, column 4).
15. Mark 7 cells adjacent to stars as X (row 7, column 3).
16. Two-option rule: Cell adjacent to both candidates (row 9, column 7).
17. Two last candidates (column 3): Eliminate 2 cells adjacent to both (row 5, column 2).
18. Two last candidates (column 4): Eliminate 1 cell adjacent to both (row 5, column 5).
19. Three candidates with two adjacent: Isolated candidate must hold a star (row 4, column 5).
20. Mark 3 cells adjacent to stars as X (row 3, column 5).
21. Column completion: 1 star needed, 1 candidate (row 6, column 4).
22. Mark 2 cells adjacent to stars as X (row 6, column 3).
23. Region completion: 1 star needed, 1 candidate (row 7, column 6).
24. Mark 2 cells adjacent to stars as X (row 7, column 7).
25. Region completion: 1 star needed, 1 candidate (row 6, column 2).
26. Mark 4 cells adjacent to stars as X (row 5, column 1).
27. Region completion: 1 star needed, 1 candidate (row 7, column 8).
28. Mark 3 cells adjacent to stars as X (row 6, column 9).
29. Region completion: 1 star needed, 1 candidate (row 9, column 6).
30. Row completion: 1 star needed, 1 candidate (row 5, column 9).
31. Mark 1 cell adjacent to stars as X (row 4, column 9).
32. Column completion: 1 star needed, 1 candidate (row 4, column 3).
33. Mark 1 cell adjacent to stars as X (row 4, column 2).
34. Row 4 complete: Mark 1 remaining cell as X (row 4, column 1).
35. Column 6 complete: Mark 2 remaining cells as X (row 1, column 6).
36. Region completion: 2 stars needed, 2 candidates (row 1, column 5).
37. Mark 1 cell adjacent to stars as X (row 2, column 5).
38. Region completion: 1 star needed, 1 candidate (row 3, column 1).
39. Row 1 complete: Mark 3 remaining cells as X (row 1, column 7).
40. Column 1 complete: Mark 2 remaining cells as X (row 8, column 1).
41. Row completion: 1 star needed, 1 candidate (row 8, column 2).
42. Mark 1 cell adjacent to stars as X (row 9, column 2).
43. Blocking rule: a star here would touch every other open cell in its region, leaving no room for the region's second star (row 2, column 8).
44. Three candidates with two adjacent: Isolated candidate must hold a star (row 2, column 9).
45. Mark 2 cells adjacent to stars as X (row 3, column 8).
46. Row 2 complete: Mark 1 remaining cell as X (row 2, column 7).
47. Region completion: 1 star needed, 1 candidate (row 3, column 7).
48. Column completion: 1 star needed, 1 candidate (row 9, column 8).
49. Mark 1 cell adjacent to stars as X (row 9, column 9).
50. Solved! Every row, column, and region has its two stars, none touching.