The Stack

Well, I’m still stuck on that last practice level. It’s a toughie.

The puzzle title is “Zipper”. It features filled and unfilled squares in a checkerboard pattern, which means that whenever you use a piece that’s more than one column wide (after taking splitting by color into account), you’ll wind up with an overhanging bit that prevents you from filling in the space beneath it. Recall that pieces (or piece fragments) of the same color stick together, potentially fusing into a piece that’s more than one column wide after you’ve placed them. This makes this puzzle unique among the practice levels in that the challenge has a lot to do with not just making the most of the pieces you’ve got, but also finding ways of getting rid of the ones you don’t want.

At one point, I was about ready to give up on this one. I hit Gamefaqs, hoping to find a nudge in the right direction. And indeed there is a guide to the practice levels there! It even features nice gentle hints, describing the general approach you have to take for each puzzle and letting you work out the details yourself. It’s always a relief to find well-written hints. Far too often the hint-writers just give everything away. Unfortunately, the person who wrote these hints couldn’t figure the last puzzle either, so it’s not a lot of use to me.