Final Press, a 6x6 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
The 3x3 nine in the top-right is fixed from the start, and almost nothing else is. Three shape-only clues hide most of the board: a wide one along the bottom that turns out to span the entire row, a wide block through the middle, and a tall clue on the left that grows into a 2x4 slab. Each settles only after the one before it, a chain three rounds deep.