Place every piece onto the board. Pieces can't overlap or hang off the grid, but you don't need to fill every square — empty cells are fine.

The board is solved once, for every row and every column, the number of filled squares in it adds up to an even number.

Count squares, not pieces. A U-pentomino placed so its top edge covers 2 squares of one row and its bottom edge covers 3 squares of the row below adds 2 to that row's count and 3 to the next row's — not "1 piece" to each.

Drag to place • click to select (+shift for multiple) • arrows move • R rotate • T flip • D duplicate • Del delete • Z undo • Esc deselect