Cat Sudoku Level 198 Hint
Look for a region whose legal cells are squeezed by two or more neighboring rows. High-level puzzles often move through exclusion, not obvious singles.
Cat Sudoku Level 198 Strategy
Expert Level 198 uses a 9x9 board with 9 colored regions. It starts without fixed cats, so the region shapes and no-touch rule do the work. Work from the tightest rows and regions before placing a cat.
Cat Sudoku Level 198 Solution
Solution cells: R1C3, R2C1, R3C8, R4C2, R5C6, R6C4, R7C9, R8C7, R9C5.