Direct elimination (✗)
When a clue says "Lord Blackwood was not in the Library", immediately place an ✗ at the intersection of Blackwood and Library.
Free tool / Logic matrix
Řešitel vražedného sudoku
Practice elimination deduction on a 4×4 murder mystery matrix. Click cells to cycle through cross-out (✗), confirmed match (✓), and empty states with automatic cross-elimination.
Deduction principles
The three golden rules of logic grid solving
The unique match (✓)
When three out of four cells in a row are marked ✗, the remaining cell must be ✓. Confirming a ✓ eliminates all other cells in that row and column.
Transitive linkage
If Lady Cynthia is in the Study (✓), and the Study contained the Poison (✓), Lady Cynthia must have held the Poison.