is still a big mystery at the moment. However, we do know at least one thing for sure:creators Turtle Rock Studios aren't making it."I think we're pretty much done with it," said Turtle Rock co-founder Phil Robb in a chat with Xbox Achievements . "It's Valve's thing now. We've kind of gone off in our own direction. So I'd kinda like to see something new being done with it, and Valve always does great stuff, but it'd be cool to go back to it as just a fan and not a developer. But I doubt you'll see anything from us."Turtle Rock started work on the original Left 4 Dead back in 2005. Valve, who was collaborating with Turtle Rock on the game, acquired the studio in January 2008 and renamed it Valve South. Valve South stayed around long enough to create the DLC for Left 4 Dead 2 . However, the former Turtle Rock team felt the urge to be independent again."Co-developing and working on one product, when both teams, two super tight-knit teams, are 800 miles apart, it's a nightmare," Robb said in an interview last year . "There was a lot of tripping over each other. At the end of the day, after we shipped [], no-one was really happy with how it worked. So we sat down with Gabe [Newell] and talked about it, and it just made the most sense that, y'know, why don't we go back to what we knew worked, which is us going independent again, and certainly they'd have work for us."Turtle Rock reformed as an independent studio in 2010 and eventually began work on Evolve . In, four players are futuristic hunters trying to track and kill a monster controlled by the fifth player. The game launched this week on Xbox One, PS4 and PC.In the Xbox Achievements interview, Robb acknowledged thatshares a lot of DNA with"If you look back atthere are some things there we felt kind of 'proved out' the theory for, like the Tank battles being one of them," Robb told XBA. "That's essentially a 4 versus 1 experience, especially if you're playing Versus mode, and we thought, 'wow, that's one of the most intense things in. We could take that and expand upon it.'", like, is a game that hasn't been announced yet but everyone believes Valve is working on.co-creator Minh "Gooseman" Le said he's seen it in action but Valve has yet to share anything about the game with the public.