Simplify the following text for a Grade 7 native English-speaking person.
Original: Puzzles constructed from multiple Sudoku grids are common .
Simplified: Samurai Sudoku is a Sudoku variation that has 5 overlapping Sudoku grids formed like a big X. These puzzles are big and take a long time to complete . Like regular Sudoku puzzles , you have to complete all 5 grids in order to complete the puzzle .