The first expansion continuing the story.
The Orange Box was released for Windows, Xbox 360, and PlayStation 3. It is still playable on modern Xbox consoles through backward compatibility, which is regarded as the best way to play the console version today. The gameplay mechanics of Portal ? How to play Team Fortress 2 today? The Orange Box
It introduced thousands of players to the Half-Life universe and established Portal’s "portal gun" mechanic as iconic. The first expansion continuing the story