Death Game+ is a commercially released platformer by Enemby Games. The goal is to die the quickest, in a large group of mostly AI participants. It was originally released in two versions, Death Game (free edition), and Death Game+, but after a much, much higher community response to the paid version, the free version was discontinued and merged. This game includes a number of interesting features, mostly a fully featured level editor. It's a great example of what a solo indie can do in about a month.
To fork and make changes, download Unity 5.0 and open "DyingIsGood" as a project. "main" is the titlescreen scenes, while others are more logically named.
Death Game was built as a test case to better understand my expected result when launching a game on steam. It is super, super rushed and not a great project to learn from.