New ideas for puzzles come to me from anywhere and everywhere. Often times they come from everyday experiences, and through ideas I contemplate at my actual job, but I also like to check out puzzle books, magazines, and websites to see what other puzzlemakers are doing. Sometimes I see a puzzle that’s great, and I want to emulate it. Other times I see a puzzle that was based on a promising idea but was (in my opinion) poorly executed, and I think I can do better. In this continuing series, I’ll share where my new puzzle ideas come from.
There is one more story about the Space Pods puzzles I wanted to tell before moving on to other things. I dug through some stuff and managed to find the puzzle from Games magazine that inspired the first Space Pods puzzle.

I thought this puzzle had some interesting ideas. However, I also thought the way it was constructed was convoluted and cumbersome. I like complex puzzles, but I find ones that have overly complicated rules to be tedious and unnecessarily torturous.
As you can see in the instructions above, three people move around the hexagonal grid unlocking doors. But each person has a certain number of specific keys, which can only go in specific locks, and once they run out they have to return to “base”, and then some of the doors re-lock, but some stay open. These details have to be summarized in a chart for each puzzle.
This puzzle is difficult because you have all of this junk that you have to keep track of. (The author even senses this – note that the instructions contain a suggestion of how to keep a record of which doors are unlocked.) Not exactly my idea of a fun puzzle-solving experience.
Despite this sentiment, I thought that there were some unique ideas contained in the puzzle that I wanted to explore. I had used two people helping each other in the Double Jumping puzzles, so why not try three people? I liked the hexagons, because it would open up more possibilities for connecting rooms together compared to a square grid. And I liked the idea of doors and locks that would be unlocked and re-locked.
I kept the three people, but now they work together, instead of sending one out, then another, then finally the third person. And the objective is no longer that just one person makes it to the goal (which never made sense to me), but that all three have to get there. I ditched the standard hexagonal grid by adding hallways. This helps connect non-contiguous hexagons and opens up the puzzle, but also precludes using a distance-to-goal heuristic while solving, which makes the puzzle harder. The most important change was simplifying the procedure of unlocking and re-locking doors. Instead of charts explaining who had what keys, the door locks would be dependent upon where the people were in the puzzle space. Thus the “chart” becomes part of the puzzle space itself (which makes it a lot easier to keep track of who can open which doors when). Consequently, the rules are vastly simplified, but the puzzles can actually be more complex, depending upon how large the space is and how many steps there are to solve the puzzle .
All in all, I think it’s a big improvement. My thanks to Sky Williams and Games magazine for inspiring me to make a puzzle using three people unlocking doors together. Oh, and in case you were wondering, here’s the solutions to the above puzzles.
