A lot has been made of the story former Valve writer, Marc Laidlaw, released last week, giving us a true taste of what a third Half-Life game, or at least a conclusion to Gordon Freeman's episodic adventures might be. In the wake of its unveiling, a lot of discussion has been made around the different story elements and some are now turning them into games or levels of games in their own right.
Half-Life: Aftermath, however, isn't something new, it's a collection of previously leaked and released game levels and information, giving us a rough idea of what Half-Life 2: Episode 3 might have been like had it eventually been released.
In the pack, created by Lever Softworks, which previously ported Xbox Live exclusive Portal levels to the PC, players will have 11 levels created by Valve itself between 2012 and 2013, presumably for a third Half-Life experience. They weren't story levels though, but more experiments of the kind of gameplay you'd find in the game.
There are another four demonstration levels put together by Lever Softworks based on Valve documents and level designs, showing off some in-game functions and NPC interactions that were expected in the game.
Also, there's some new weapons that were experimented with for a future Half-Life game. There's a new Combine laser gun that can shoot through walls, a new Combine armored soldier to take on and a new City Scanner tool with a laser gun of its own attached.
If you want to play it yourself, you can download Aftermath from ModDB, or watch the video above for a run through by the Valve News Network.