Multi Sudoku (604)

Other names: Double Doku

Instruction:

Place a number from 1-9 in each empty cell in the overlapping grids such that each row, column and marked 3×3 box contains each number exactly once.

Reference: WPF (1)

Examples:

WPF Sudoku GP 2016 - Round 3 (100)

Parent puzzle:
Sudoku

Child puzzles:
Double Doku
Interconnected Classics Sudoku
Matryoshka Sudoku