Level 254 solution

Solver-verified route

1. Place Piece 1 across column 5 row 6, column 4 row 7, column 5 row 7.
2. Place Piece 2 across column 1 row 8, column 2 row 8, column 3 row 8.
3. Place Piece 5 across column 4 row 8, column 5 row 8, column 6 row 8.
4. Place Piece 3 across column 4 row 1, column 5 row 1, column 5 row 2.
5. Place Piece 4 across column 3 row 2, column 4 row 2, column 3 row 3, column 4 row 3.
6. Place Piece 6 across column 6 row 2, column 7 row 2, column 6 row 3.
7. Place Piece 7 across column 5 row 4, column 6 row 4, column 5 row 5.

Part of the "Master columns" chapter. The solver certified 1000+ solving lines with 77% of in-between placements being dead ends, for a difficulty score of 18.3 (grade 4 of 5).