The most believable rumor comes from Valve News Network’s Tyler McVicker again. Supposed Left 4 Dead 3 character concept art from 2013

Was this a legitimate mistake or an intentional tease?

The image was quickly removed and replaced with a different one. The tutorial included a screenshot of his Windows Explorer favorites, with a ‘left4dead3’ folder listed at the top. Later that year, Valve fansite ValveTime reported that employee Tristan Reidford appeared to leak proof of L4D3’s development after publishing a Destinations Workshop Tools tutorial to Steam. A direct connection between the files and the game’s development was never found. Whether he was supposed to be an NPC or a Survivor is unknown. Valve News Network’s Tyler McVicker unearthed several references and assets in its source files, including a new special infected enemy called The Nocturnal, a day/night cycle, and an older male character. In 2016, it seemed like Valve had slipped up by including possible L4D3 leaks in an HTC Vive benchmark tool built using their Source Engine.

We were recently teased with an impressive game trailer that seemed almost official but unfortunately wasn’t, as confirmed to us by Valve itself. The series’ lead writer Chet Faliszek hinted at the possibility of a third installment in an interview with Eurogamer back in 2012, but we’ve had nothing but radio silence from official channels since. Is there proof Left 4 Dead 3 is in development? It's not Left 4 Dead 3 in name, but it's likely the closest that we'll get anytime soon, so it's worth keeping an eye on if you're really, really hungry to bite into some zombie-killing co-op. It's is a more visually polished game, of course, but its basic parts are identical: four-player, run-and-gun shooting through criss-crossing urban and outdoor post-apocalyptica (in the first 15 minutes: apartment, rooftop, construction site, haphazard parking lot), conventional military weapons, and a procedurally-driven 'Director' AI overseeing the action, pulling the strings.' 'The shooter unapologetically walks in the footsteps of what we played in '08 and '09. Evan has played the co-op zombie game Back 4 Blood and cannot stress enough that it's basically Left 4 Dead 3. So Valve isn't making Left 4 Dead 3, but Turtle Rock Studios totally is, though under a different name.

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