It can be difficult to find time to finish a video game, especially if you only have a few hours a week to play. In our biweekly column Short Play, we suggest video games that can be started and finished in a weekend.

Every four months there is an event called Ludum Dare, where participants try to make a complete game from scratch in 48 hours, based on a particular theme. It’s a difficult task for a group, let alone a single person, to get a game to a finished state in that amount of time. Often the best games from these jams tend to be a distillation of a specific game mechanic, plot point, or idea. Windowframe, made by Daniel Linssen during the 35th Ludum Dare in 2015, is a great example of this, focusing on one very specific and clever concept.

It’s a 2D puzzle platformer with a strange conceit: what if adjusting the size of the window the game ran in altered the game’s environment? Windowframe lets you pin an edge of the game window in place by throwing a stake at it. Clicking and dragging on the stake in the window edge also lets you shrink the window from that direction.

When an edge is pinned with a stake it acts like an impassable barrier. For the left and right edges, they become walls that the player can jump off of. Meanwhile, when the bottom edge is staked, it acts as a floor allowing you to traverse over holes or spikes you couldn’t before. And while the window edges are pinned, you’re able to move them in to make the window smaller, but not out to make them larger. You can unpin an edge by removing your stake, but doing so removes all of them, not just the specific stake you might want. It also doesn’t happen instantly, instead requiring you to hold the ‘R’ key for a few seconds while remaining stationary. Only then are the stakes are removed.

This becomes an important part of the game’s level and puzzle design. While you start the game with six stakes, more than enough for all four window edges, you start to lose them as you progress — and they’re gone permanently. Every few levels you have to kill a vampire, and with each kill you lose one of your precious stakes.

Because of this, early in the game you’ll feel pretty powerful. You can toss around your stakes rather willy-nilly, pinning all of the window edges while still having stakes to spare. But as you get further into the game — especially when your stake supply dwindles to three or fewer — the levels become more of a puzzle. Figuring out those puzzles slowly teaches you the nuances of how to better use the stakes, and by the time you are down to one stake you’ll feel powerful, but in a different way. Now you’ll have a greater understanding of how to best use your abilities, even though you’re technically limited at this point.

Windowframe, as a game made in just 48 hours, could have easily been a tech demo of a clever game mechanic. Instead it’s a testament to how important level, puzzle, and game design working together can effectively teach the player, and make a truly good game.

Windowframe was created by Daniel Linssen. You can get it on itch.io for pay what you want on Windows PCs. It takes about an hour or two to finish.