Game news site Siliconera was teasing over the weekend that they had an unannounced Square Enix game to reveal to the world, and that game is Catacombs. Initially developed by Cavia--the developers of Nier--before they were closed down, it's a 3rd person action game that was set to take place in New York's Museum of Natural History. Their source was someone who worked on the game before Cavia was closed, so they aren't sure if the game will ever be released.

I suggest checking out Siliconera for the news as they will be featuring more details on what makes the game unique through the week. We don't really get to see a lot of what developers abandon, if this indeed doesn't get released.

Source: Catacombs - The Game Cavia And Square Enix Were Working On After Nier | Siliconera