Cat Sudoku Level 4 Hint
Find a colored region with only a few safe cells, then compare those cells against the row and column limits.
Cat Sudoku Level 4 Strategy
Easy Level 4 uses a 6x6 board with 6 colored regions. It starts with 2 fixed cats to anchor the solve. Work from the tightest rows and regions before placing a cat.
Cat Sudoku Level 4 Solution
Solution cells: R1C2, R2C5, R3C1, R4C4, R5C6, R6C3.