Coastline to Atmosphere - A mod set in the Half-Life 2 universe, following Gordon Freeman after the events of Half-Life 2.Black Mesa originally released as a free mod in September 2012, and later had a full commercial release on Steam in March 2020. Black Mesa - A third-party recreation of Half-Life (1998) that was made in response to the release of Half-Life: Source (2004), a port of the original game to the Source engine.Instead of a portal gun, the player solves puzzles using a mix of these gels that they can spray onto surfaces with a tool they carry. Aperture Tag - A modification based on Portal 2 that recreates the essence of the game Tag: The Power of Paint, the inspiration for the various gels used in Portal 2.This list is divided into single-player and multiplayer mods. This is a selected list of Source engine mods (modifications), the game engine created by Valve for most of their games, including Half-Life, Team Fortress 2, and Portal, as well as licensed to third parties.
