Thirteens everywhere...

About the game

The robot JSK-13 has to reach a flag, but it suffers from triskadekaphobia, the fear of the number thirteen, and the board is covered in thirteens. A wall of 13s is deadly: touch one and it breaks down. It cannot be steered by hand. You steer it by writing a program for it, and then you watch it run.

The language is tiny and the game teaches it as you go. The first level introduces one command, run, and the next adds left and right. After that come loops, which repeat what is inside until the road ends, and then conditions that let the robot check what is ahead, to the left or to the right before it decides. Each level also gives you a budget of commands, shown at the bottom of the editor as "Commands: 3 of 5", and the real challenge is to solve the puzzle with as little code as possible.

There are thirteen levels, and the last ones are mazes you solve with a short loop and a few well-placed conditions. It was made for js13kGames 2024 by @mallo_c, and the graphics are plain on purpose.

Playing it here

Click Play, read the introduction and press OK. Type your program on the left, press Run and watch the grid on the right. If the robot does not reach the flag the game says so, and you can edit and try again. The Speed button cycles between slow and faster speeds, which helps once a long loop works. Use a keyboard: there is no on-screen one.

Controls

A few things worth knowing

Start with the example. Each level opens with a short text and an example of the new command; the example is almost always the answer for a level that is just about the new idea.

Loops save commands. The budget is tight enough that a loop is often the only way to fit the whole path.

Think in turns, not steps. Check what a scan command sees before you move, and let the program decide at each tile instead of counting tiles by hand.

Credits and licence

Thirteens everywhere... was created by @mallo_c and is released under the ISC licence. The licence text is linked from this page.