Sky Slash (2013) was three separate entries built in Unity for the second season of the One Game A Month game jam. The three games were built in mechanical episodes, where each episode was more technically advanced than the previous.
In a sense this was three different stages of development (1 month, 2 months and 3 months) but they were kept as three separate projects to better represent the one game a month rule.
All three are available here (1), here (2) and here (3) with a total of 4 400 downloads