Pieceword

A Pieceword (aka Jigcross, Jigsaw Crossword and Kross-Piece) is a completed crossword that has been divided into 3×3 pieces, which the solver must put into their correct places in the grid with the aid of just the Across clues. The solver needs to deduce the location of the black squares as well as the answers to the clues.

The solver knows that the grid is symmetrical. Typically, the grid will have biaxial symmetry (top mirrors bottom, and left mirrors right), but the puzzle can be made more demanding with a central symmetry grid (top left mirrors bottom right, top right mirrors bottom left).

No letter counts are given, as this would too easily reveal information about the location of the black squares, but we play fair by avoiding answers that are hyphenated words, phrases or proper nouns. 

The more interlocking the grid, the easier it is for the solver, but the length of words in the grid also has a bearing on the puzzle’s difficulty. Short words yield little information about surrounding blocks, but a long word will unlock a whole section of the grid.