Left 4 Dead & Codename Citadel - Feb 2020 Leaks

Today on Valve News Network, we take a look at some engine-level leaks that were found within the February 6th beta update to SteamVR, the one that added the redesigned VR dashboard. These leaks include references to an updated AI navigation system, written specifically for Left 4 Dead between 2013 and 2017, and this navigation system being moved to the base-engine layer of Source 2, then ported over to Half-Life: Alyx, and the currently unknown Virtual Reality title, Codenamed Citadel.  
 

Left 4 Dead & Codename Citadel - Source 2 - Feb 2020 Leak (YouTube)