A Dota 2 subreddit group went on a tour of Valve’s offices recently. A photo from the tour group has now surfaced and is allegedly of a developer’s monitor showing references to Left 4 Dead 3 and Source 2.
Reddit user r_dageek posted the photo on the Dota 2 subreddit, noting the references to Left 4 Dead 3 and Source Engine 2. CyborgMatt posted a zoomed-in version of the image which shows text reading “[Source 2] Restored L4D3’s devtest unit test. Ran locally 6 times without an assert. There may be so…”. There is also a timestamp of August 5th.
Gabe Newell confirmed the existence of the Source Engine 2 during a Q&A session with a group of fans from 4chan’s /v/ board in November last year.