Flower Sudoku is a member of the Gattai family of [[Sudoku Variant]s. The format was designed by udosuk.
Although it is possible to have a Flower Sudoku with only 4 constituent Sudokus, the most common format has 5 constituent Sudokus, creating a dense overlapping region in the center.
The overlapping Sudokus are arranged like this:
Flower Sudokus do not need any givens in the overlapping regions. When you try to solve this puzzle, remember that there is a 5th Sudoku in the center.