The theme for the game jam I originally created this game for was "Unstable". I was originally thinking of creating a game involving nuclear fission, where you had to be careful about creating unstable nuclei that split. But I looked at the Wikipedia page for stable and unstable nuclei and was like nope, that would be too much to hard-code into one game, and players can't tell at one glance what nuclei would be stable or unstable - they would have to look up an online or in-game reference. So I thought of creating a system where at one glance you could tell if an object was stable or not. This led me to think about odd and even numbers - you could easily tell if a number is odd or even, right? - and this was how this game came about.