The video blogger imported Mirage, one of the most famous map from CS:GO into Source 2 using Half-Life:Alyx tools and certain scripts. The result was published on YouTube.
Source 2 is a Valve game engine that is used in Dota 2, Half-Life:Alyx and other games. The current CS:GO version is made on the previous software version of Source.
At the end of March, video blogger Tyler McVicker announced that the CS:GO will move to Source 2 within the next few months. Mike Grzegesik said that the CS:GO would move to the new engine this summer.