Half-Life 2: Episode One

Global, Action, Steam Achievements, Partial Controller Support, Steam Cloud, Stats, Single-player, Captions available, Includes Source SDK, Commentary available, Remote Play Together, Tradable

Link to the game in Steam

Half-Life 2: Episode One - Gamescon

Half-Life 2 has sold over 4 million copies worldwide, and earned over 35 Game of the Year Awards. Episode One is the first in a series of games that reveal the aftermath of Half-Life 2 and launch a journey beyond City 17. Also features two multiplayer games. Half-Life 2 not required.