When the themes came out I took the opportunity to watch the "Dr Strangelove" movie. I knew about it but had never seen it. I thoroughly enjoyed it and really wanted to try to incorporate that tightly into my game. This turned out to be double edged. Some ideas came easily from that theme but it also felt a bit constraining as well.


I set out to make a stealth game, with you creeping into the facilities and trying to avoid detection. I spotted on day two that this is hard to make fun. Stealth tends to imply a lot of watching and waiting which is hard to make fun!

When I took a break for the night I thought of the "swapping" mechanic (yep, stolen from "the swapper") and suddenly I saw this was a good way out. Now when one guy is waiting you can be doing things with the other guy. Also, the you have to consider the inactive guy because he can sometimes be in danger of being discovered.

This opened up the game and allowed me to find the fun parts. It also changed it into a puzzler rather than a stealth game. That worked well and allowed me to experiment with level design so I was happy with that.


I found the fabulous war and destruction pictures on Deviant Art. I knew I wanted to incorporate those but they were too serious for my overall theme. Happily I found a way to switch that also with the sudden jump to Dr Strangelove!

I totally underestimated the time needed to develop the level graphics. Generating tilesets and dynamic objects takes a long time. The door alone took well over an hour and that's a lot for a single item. The tileset is nowhere near polished enough but I suspect there's another week in there just for that!

Title and Story

There was a much bigger story element to the game that I never added. The overall idea was to echo the Dr Strangelove theme of the futility of the mutally assured destruction (MAD) strategy.

The name comes from the "Nash equilibrium", which is a specific state in game theory where both players know the strategy of the other and know that there is nothing to be gained by changing strategy. This is the stable state for MAD and so I wanted to play with that idea.

The story was supposed to be relayed by Strangelove and also by having snippets of speech from the guards. However, I didn't write Strangelove's text until late in the day I was simply too tired to add the creative part (lesson learned - do creative work up front!). So I just ommitted that.

I also ommitted the guards giving story hints. I discovered early on that I needed to use the guard's speech to let the player understand the guard's "thinking" and therefore understand the model of how they would operate. I realised that if I peppered in random story bits then it would hide this so I just kept them talking about what they were doing or thinking

Level Design

I worked on this a lot. I wanted each level to have a couple of elements that the player would learn about the puzzles. I took this from "The Witness" game. This worked well but meant that it took a long time to design and tune each level, so I didn't get many of them done.

It also meant that I had additional aspects that I built but never added to a level. The guards will actually get tired and go to sleep. When they do they call in someone else to "swap" out their patrol. This is fully implemented but I could not easily think how to teach the player how it worked and also generate a meaningful puzzle out of it.

I know if can be done but I think I would have needed several additional levels to introduce the idea properly so I left it out in the end.

My Two Favourite Bits

1. I love the hat switching. I'm so glad I found that approach.
2. The guards saying "Keycard!" when opening a locked door. Helps the player to understand why the guard can open a door that they cannot and also adds a bit of character.

My Two Regrets

1. Missing the story in the main game. I've since written this and it only took an hour but I learned that I really need to do this at the begining
2. The pymunk inconsistency! Aargh! It's not even used but my serge engine will try to load and initialise it when it finds it is installed.

Thanks again to all for playing and rating my game!

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This was a great game, well done. I really liked the intro to the game ... I laughed out loud when Peter Sellers head suddenly sprung into view and we saw that it was all just a movie running on an old projector :).

I think it was really good that you omitted the guard/story thing ... I definitely only figured out that the guards had certain behaviours based on what they said (the use of "Keycard!" was particularly apt).

What you said about level design: I think it's a great thing when there are things that you spend a good amount of time implementing and then totally leave out of the game: this shows creative discipline to throw away an idea when it's not working, or not adding anything to the overall experience, even when you feel like if you leave it out, then you wasted all that time for nothing.

Pymunk inconsistency: I was working with 4.0.0 and realised towards the end of the week that 5.0.0 had a totally different set of functions than those I was using. I ended taking a cue from one of Tee's old games, in which he bundled the static libraries for pymunk 4.0.0 in with his game. I'm guessing that this worked fine for everyone, as I didn't get any complaints :).