At the 2014 Game Developers Conference, Valve employee Sergiy Migdalskiy showed off a Source 2 physics debugging tool being used in Left 4 Dead 2. Images of this were leaked onto the internet in early 2014.
The first engine tech demo was created in 2010 by remaking a map from Left 4 Dead 2. Plans for a successor to the original Source engine began following the release of Half-Life 2: Episode Two in 2007. Since then, Valve's Artifact, Dota Underlords, and Half-Life: Alyx have all been made with the engine. The engine was announced in 2015, with the first game to use it, Dota 2, being ported from the original engine that same year.
Source 2 is a video game engine developed by Valve as the successor to the original Source engine.
