Bird Sudoku Level 155 Hint
Pick a row, column, or habitat with a low remaining count, then check which of its perch cells are blocked by open diagonal flight lines.
Bird Sudoku Level 155 Strategy
Hard Level 155 uses a 9x9 board with 29 perch cells, 7 blockers, and 7 habitats. Use the row and column counts first, then test each open diagonal flight line.
Bird Sudoku Level 155 Solution
Bird positions in the solution: R1C6, R1C9, R2C1, R3C3, R3C9, R4C5, R5C1, R6C5, R7C1, R7C2, R9C4.