It is normal for the developer of a game to remove some of the stuff that they have created for the game so that it does not feel too crowded. When the developer of Alien: Isolation wrapped up the game, they also took away some dialogues and audio from the game.
These extra files usually stay hidden forever but in the case of Alien: Isolation, a web developer managed to get his hands on them and has now posted them online for all the fans to enjoy. Of course, these files will not change how the game ends or the story of the game but it does shine a little more light on the game.
Matt Flier reveals that the found some audio and dialogues files when he was looking through the game’s file, you can read and hear them here if you are interested.
While the files will not have any impact on the game, it does give us a better idea of what was happening at Sevastopol before Ridley arrived. We also got to learn more about some of the characters in the game as well.