Magical Mystery Murder Quest

Mystery Magical Murder Quest is an open-world parkour action game (a fusion of games like Assassin's Creed and Minecraft) and is a spinoff of the Crystal Warriors series. It also ties into Naegi's role in The Mysterious Seven Project.

Story
The story begins with an alternate timeline Homura watching as the real world and Voidspace get ripped into one, creating a gigantic city that spans the entire planet, simply titled "Happy City." In this timeline, the Crystal Warriors were defeated, and Mami Tomoe and Kamina were mercilessly killed far prior to the events of Fast-Food Chain From Another Dimension. Homura, as a last resort, escapes the timeline and searches through other timelines in hopes of finding one where Madoka - and the rest of the Crystal Warriors - succeeded.