Most of my work on 100RTBD is pretty iterative. Like this challenge I'm working on right now, for instance! My design doc states the following "A challenge room where the player dies if he's not in darkness". That seems vague enough, but I've figured out what it meant; A spot of darkness moves around the room and you have to stay behind it, otherwise you fail the challenge. Then I've started playing with the idea and figured out that jumping and falling does not work very well with the whole 'follow the dark circle' mechanic, since you have less control over these things, so now I'm reworking it a bit!
Most of the game is like that, I start from 'old' ideas, interpret them, then rework them!
Time spent on the project so far: 543 hours
Currently working on: Continuing the story
Screenshot after the jump: A challenge in the dark