GameSpot conducted a Q&A with Valve's Robin Walker, a designer/programmer, and dug up quite a few new details on Half-Life 2: Aftermath, the first expansion for the game. All the action takes place in City 17 with a rather cataclysmic event about to occur. Plenty of the characters return (including Dog) and Aftermath will answer some questions gamers had regarding the Half-Life universe but at the same time creating many new mysteries. Walker also hammered home the point that there are certain new abilities that will be realized that'll play a big role both in the singleplayer and the multiplayer.

GS: Half-Life 2 was a universally acclaimed game, but was there anything in the game that you wished you had more time to work on that you're setting out to fix or add to in Aftermath? RW: The biggest regret we had about Half-Life 2 was that you didn't spend enough time with the major characters. Players spent small sections of the game with allies, and interactions with them were fairly constrained. As a result, this is the first challenge we set out to tackle in Aftermath.