Edmund McMillen, I'm the designer and artist for Coil.
What sparked your game development flame?
Coil was inspired by the death of my father and my terminally ill grandmother, but that sounds like a weird response to that question. The prettier answer would probably be, Coil was inspired by the loss of a loved one, I was confused about the feelings I had about the situation and the idea of death so I wrote about my feelings in game form.
Where and when did the concept for Coil originate?
Coil's design started in mid 07 after I finished working on Triachnid. I was intrigued by the amount of emotion I was able to express through Triachnid's design and wanted to see if I could design a more abstract and autobiographical piece that played around with those emotional aspects.
Over the course of development, what was Coil’s most serious issue and how was it resolved?
The only serious issue we ran into was caused by Florian's mandatory army duty, the game was put on hold for 6 months. Coming back to it was a little difficult because my feeling had changed slightly, but I was able to take it in another direction and finish it shortly after Florian came back.
What’s one thing you did wrong that you feel could have been avoided?
The Title screen puzzle was something I thought was extremely important, but I didn't put into consideration that a player might solve it without knowing how they had done it or even realize it was a puzzle. I used this "movement puzzle" between each level break and I found that a lot of people assumed they were loading screens. If I would have tested the game more I could have found a way around this, but I was too eager to get the game into the hands of the public. The problem wasn't ever fixed because I'm lazy.
How long was Coil in development? How much development time remains?
Not counting the break we had to take, Coil took about 2 and a half months to finish. Coil is done.
What was used to make the game and what tools aided in development?
Flash.
What's the main thing you think makes your game fun?
I can't say that everyone would find Coil "fun" but I think a lot of the lack of hand holding and emotional theme create a magical non-game experience that can be very enjoyable. Personally I think the best thing about Coil is the fact that it not only gets you thinking and questioning things but also feeling things that wouldn't normally be felt by playing a video game.
Is there anything about Coil that you would like to reveal to other developers?
There was an 8th phase that was cut from the game due to self imposed time constraints, it was a 2nd conception stage that came before the final phase of the game, the stage was very graphic... its too bad I couldn't add it in time, but 7 feels like a better number anyway.
What’s next for you?
I’ll be working on my 3rd autobiographical piece later this year, its called Huck and its about my father. Aside from my "alt games" I'm also working on Super Meat Boy for Wiiware, No Quarter for PC and Gish 2 for an unnamed console.