Marble Thread, a 8x8 Patches puzzle
Arrow keys move. Enter starts a rectangle; arrows resize it; Enter places it. Escape cancels. Delete removes a patch. Control or Command Z undoes.
About this board
Twelve clues, every one with a number, and five of them have only one possible patch: the 4 in the top-left, the 9 near the top-right, the tall 4 and the square at the bottom-left, and the 4 in the bottom-right corner. A tall 6 runs down the middle like a vein through marble, splitting the board into a 3x4 block on the left and stacked three-wide pieces on the right.