Half-Life 2: Episode Three, the third and final instalment of the Half-Life 2 episodes, was expected to follow soon after Episode Two, as Valve had stated that they aimed to release a new episode every six to eight months. However, as of March 2012, three pieces of concept art are all Valve have shown of the next game. Since then, Valve has released four games, and it currently has two in development, with only one of these, Portal 2, being set in the half-life universe.
Some fans believe Valve has scrapped the episodic model and is now working on a full sequel entitled Half-Life 3, but Valve employees have consistently refused to comment on the status or nature of the next Half-Life game, much to the displeasure of their fanbase. Despite general satisfaction with the games Valve has made since Episode Two, the next Half-Life game continues to be their most anticipated title, and with the long-awaited release of Duke Nukem Forever in 2011, it has become gaming's most infamous case of continuing vaporware.