Portugues
Do Not Make 13
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About the game
Do Not Make 13 gives you almost nothing to read: a ball on the left edge, a goal on the right and a few digits and plus signs floating in between. Your only tool is a line that you draw from the ball to the goal. The line cuts the field in two, one half red and the other blue, and every symbol ends up on one side or the other. When the line reaches the goal, the symbols on each side try to combine into sums, and the one total they must never reach is in the title: 13. A 1 and a 3 together, an 8 and a 5, or 7 + 6 are all enough to fail, and the game will show you the sum it found and send you back to try again.
The game never explains itself in words. You find out how the symbols combine by drawing a line and watching what comes out, and every later level reuses what you worked out, with more numbers, more signs and less room. A 6 and a 9 can stand in for each other, and a plus sign can work as a times sign too, so there are more ways to make 13 than the first level suggests.
There are thirteen levels, with a title screen, a new pair of colours for each level and a short ending. The picture is drawn with WebGL in a sharp, high-contrast style with a red and blue fringe on everything, and the music is generated by the code while you play.
Pim Schreurs made Do Not Make 13 for js13kGames 2024, where the whole game had to fit in 13 KB.
Playing it here
Click Play, then click once on the game to wake it up and start the music. Press the mouse button next to the ball, drag a line across the field to the goal and release. If a side adds up to 13, the sum is shown and the line is rewound; press Restart in the corner to start over, then try a different path that sends the troublesome numbers to different sides. The game remembers the level you reached in this browser. On a phone, play in landscape and tap the screen once to turn the sound on.
Controls
| Input | Action |
|---|---|
| press, drag and release | draw the line from the ball to the goal |
| Restart button | start the level over |
| touch | the same, with a finger (landscape works best) |
A few things worth knowing
Think about pairs. Look for the numbers that can reach 13 together, like 1 and 3, and decide which side of the line each of them will be on.
Keep the line moving to the right. The line is drawn from left to right and has to end at the goal, so plan the path before you press.
The first level is the tutorial. If a line leaves both digits on the same side, a faint hint shows where the line should pass.
Credits and licence
Do Not Make 13 was created by Pim Schreurs. The game is released under the MIT licence; the licence text is linked from this page.