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Oh no, I broke a mirror! That means bad luck or something, doesn't it? Can you help me fix it?

I made an image of my mirror below. You have to move some pieces so that a laser pointed in the direction of the red arrow will bounce on the mirror lines and go out at the green arrow.

Mirrors (each mirror is one diagonal segment) can only be moved one unit horizontally or vertically. The goal is to make as few moves as possible.

enter image description here

Details to prevent "lateral thinking" answers. Mirrors cannot be rotated. All the mirrors are designed to be 45 degrees from the horizontal. Any deviation from +45 or -45 degrees is accidental and shouldn't be interpreted as the key to the solution. The laser bounces upon impact with the black lines like all physics-law-abiding lasers would. The laser always moves either horizontally or vertically. You can either move a mirror one unit North, one unit East, one unit South, or one unit West. If the laser escapes the labyrinth without reaching the green arrow, you lose. No smoking or space-warping 10 meters from this puzzle.


This puzzle was inspired by a board game where you have to move mirrors in similar ways.

I hope it's fun to solve.

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  • $\begingroup$ KHET? I love that game. $\endgroup$ – OldBunny2800 Jan 10 '18 at 1:50
  • $\begingroup$ @OldBunny2800 I think so (I don't have the game, I saw it somewhere). $\endgroup$ – R.M Jan 10 '18 at 1:52
  • $\begingroup$ It adds more complexity, as different pieces have different mirrors on different sides. Pyramids only have one mirror, so two sides bounce and two sides are walls. Scarabs, like your black lines, reflect in either direction. Other pieces don't have mirrors. And, rotation is allowed. By the way, nice puzzle! $\endgroup$ – OldBunny2800 Jan 10 '18 at 1:54
  • $\begingroup$ @OldBunny2800 yeah, that must be it. Thanks! $\endgroup$ – R.M Jan 10 '18 at 1:57
  • $\begingroup$ This one reminds me of the logo of Puzzling SE. $\endgroup$ – Weijun Zhou Jan 10 '18 at 10:20
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Unless I'm missing something obvious... Just one!

solution

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  • $\begingroup$ Good catch! I was getting close, but you beat me to it. $\endgroup$ – gnovice Jan 9 '18 at 21:17
  • $\begingroup$ Thanks. I had a couple more 2-move solutions I was going to post when I stumbled across it. $\endgroup$ – Toast Jan 9 '18 at 22:07
  • $\begingroup$ Oh. Wow. When I was making the puzzle, I displaced 2 mirrors and was very convinced that 2 was the best solution. Nice! :) $\endgroup$ – R.M Jan 9 '18 at 22:42
  • $\begingroup$ "Hoped no one would notice." Welcome to Puzzling SE! $\endgroup$ – Jay Jan 10 '18 at 13:00
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Just two moves is the best I can do...

Solution #1:

enter image description here

Solution #2:

enter image description here

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