Source Entities:Games

The Source engine has a large selection of games on it, and three of them were released at the same time. Some are "built off" each other in a branching and not-wholly-linear path. Functionality also is occasionally wildly different between games due to Valve's seemingly ever-shifting method of maintaining code.

Since it's not perfectly clear, on Source Entities, all text along the lines of "available since X game" means "available in X game, and every game that was released afterward". Some people instead think this simply means that it's been in every Source game since the release of one game, implying the feature was backported (usually not the case).

Supported games

 * Alien Swarm
 * Counter-Strike: Global Offensive1
 * Counter-Strike: Source
 * Day of Defeat: Source
 * Half-Life 2
 * Half-Life 2: Deathmatch
 * Half-Life 2 Episodes
 * Left 4 Dead
 * Left 4 Dead 2
 * Portal
 * Portal 2
 * Team Fortress 21

Possible games
These games might be considered for documentation on this wiki once the main 12 are finished. This list is not necessarily complete but they are the games most likely to be incorporated. For the time being, the specifics for supporting these games have not even been worked out.
 * Alien Swarm: Reactive Drop1
 * Age of Chivalry
 * Black Mesa1
 * BrainBread 2
 * Contagion
 * Dark Messiah of Might & Magic
 * Day of Infamy
 * Dear Esther
 * Dino D-Day
 * E.Y.E: Divine Cybermancy
 * Fistful of Frags
 * Garry's Mod1
 * INFRA
 * Insurgency
 * No More Room in Hell
 * Nuclear Dawn
 * Pirates, Vikings, & Knights II1
 * Sin Episodes
 * Synergy
 * The Ship
 * Vampire The Masquerade - Bloodlines
 * Zeno Clash

1 - These games seem to still be under significant active development. Keeping the documentation up to date is very important.

Orange Box
The Orange Box is the name given to a package of games released by Valve all on the same day. It's made up of Team Fortress 2, Portal, and Half-Life 2: Episode 2 (along with HL2 and Episode 1 bundled) which were all close to being finished at the same time anyway. On Source Ents, due to the fact that the HL2 Episodes run on the exact same code (in source and binary), "The Orange Box" only refers to TF2 and Portal 1 (excluding Ep 2), and things that were added in all three games at once will be noted as being added in the HL2 Episodes because they came first and technically, all code new with Episode 2 was really just an update to the Episodic branch. While this is odd, it clears up any ambiguity.

The Half-Life 2 series
"The Half-Life 2 series" refers to all these games: Portal is included because it comes with nearly all code in the Episodic branch. Evidence exists in that many Half-Life 2 NPCs and weapons may be spawned, and if equipped, the HEV suit shows the Episode 2 flashlight HUD element. Portal 2 is not explicitly included, but many things in Portal 1 ended up being available in Portal 2 as well.
 * Half-Life 2
 * Half-Life 2: Deathmatch
 * Half-Life 2 Episodes
 * Half-Life 2: Lost Coast
 * Portal

Engines
Originally, Source Entities was to also document GoldSrc and Source 2 material, though it's being considered if splitting up by engine into sister wikis would work better. Support for Quake is not being considered.

"Historic" notes
Commonly, VDC notes things that were added to Source at the time of a certain game, yet these features were also backported to older Source games. SE will not do this because it creates ambiguity. Being clear and accurate is more important than an otherwise trivial fact about a feature.