Bulldoku Level 420: Walkthrough & Solution
Step-by-step Bulldoku level 420 guide (8×8). One pup per color, row and column, no touching. Difficulty 44.3.
Play Level 420Step-by-step logic
1. Step: place pup (row 8, column 2)
After crosses, the blue region has only one legal cell — row 8, column 2. Place a pup there. Mark crosses along the row, column, and neighboring cells (see the board).
Board after step 1 2. Step: place pup (row 7, column 4)
After crosses, the green region has only one legal cell — row 7, column 4. Place a pup there. Mark crosses along the row, column, and neighboring cells (see the board).
Board after step 2 3. Step: mark X (line reservation)
Several regions share the same rows or columns — other cells on those lines are impossible. Mark them with X.
Board after step 3 4. Step: mark X (line reservation)
Several regions share the same rows or columns — other cells on those lines are impossible. Mark them with X.
Board after step 4 5. Step: mark X (line reservation)
Several regions share the same rows or columns — other cells on those lines are impossible. Mark them with X.
Board after step 5 6. Step: mark X in row 1
The cyan region is confined to row 1. Mark X on cells in that row that belong to other regions.
Board after step 6 7. Step: mark X in row 1
The cyan region is confined to row 1. Mark X on cells in that row that belong to other regions.
Board after step 7 8. Step: mark X in row 1
The cyan region is confined to row 1. Mark X on cells in that row that belong to other regions.
Board after step 8 9. Step: place pup (row 2, column 7)
After crosses, the pink region has only one legal cell — row 2, column 7. Place a pup there. Mark crosses along the row, column, and neighboring cells (see the board).
Board after step 9 10. Step: place pup (row 1, column 5)
After previous pups, row 1 has only one free cell — column 5. Place the cyan region's pup here. Mark crosses along the row, column, and neighboring cells (see the board).
Board after step 10 11. Step: place pup (row 3, column 1)
After previous pups, row 3 has only one free cell — column 1. Place the mint region's pup here. Mark crosses along the row, column, and neighboring cells (see the board).
Board after step 11 12. Step: place pup (row 5, column 3)
After previous pups, column 3 has only one free cell — row 5. Place the orange region's pup here. Mark crosses along the row, column, and neighboring cells (see the board).
Board after step 12 13. Step: place pup (row 6, column 6)
After crosses, the lavender region has only one legal cell — row 6, column 6. Place a pup there. Mark crosses along the row, column, and neighboring cells (see the board).
Board after step 13 14. Step: place pup (row 4, column 8)
After previous pups, row 4 has only one free cell — column 8. Place the yellow region's pup here. Mark crosses along the row, column, and neighboring cells (see the board).
Board after step 14
Final solution
All pups placed correctly: R1 C5, R2 C7, R3 C1, R4 C8, R5 C3, R6 C6, R7 C4, R8 C2
Similar difficulty levels
FAQ
- How do I solve Bulldoku level 420?
- Follow the 14 steps above: find forced placements first, then mark impossible cells with X.
- Where can I play level 420 online?
- Click "Play Level 420" to open the free browser game with this exact board.