Accidental Valve Leak Confirms Source 2 Engine and Left 4 Dead 3

We can’t imagine that Valve is too pleased about this leak, but one thing’s for certain: millions of its fans will be. Thanks to some Reddit Dota 2 fans who had the opportunity to take a tour at Valve prior to The International‘s kickoff on Wednesday, we get our first big hint (it seems highly unlikely that this is faked) that the company’s Source 2 engine is in heavy development, along with Left 4 Dead 3.

The leak occurred in the most inadvertent way, and as of the time of writing, it doesn’t even seem like whoever took the picture realizes the gold they captured. The picture in question is seen below. It’s of a commit log that summarizes changes each developer has made to a project’s respective source code.

The line in question comes courtesy of developer Ted Carson:

[Source2] Changed L4D3’s test_networking unit test to use the devtest level again. Ran assert-free…

The fact that either of these two things exist isn’t surprising, but that doesn’t make this less interesting. The Left 4 Dead series has a huge following, and given how many times Valve has put L4D2 on sale, it’s nice to know for sure that a third iteration is en route. On the game engine front, Valve has made reference to Source 2 in the past, so again, no real surprise here. As long as Valve hasn’t given up on the Half-Life series (I wonder sometimes), it seems highly likely that the next game in that series will be built using Source 2 as well.