Portal: Prelude

Game Details

The unofficial prequel to the game Portal.

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This game requires that you own the Source engine game Portal. Click here for a full list of games that meet this requirement.

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Removed Original Music to stop copyright infringement



Its story revolves around the pre-GlaDOS epoch, even before she was plugged in. At this time, test subjects were monitored by real Aperture Science employees whose work was tedious, lengthy and repetitive. This is why they decided to build a great artificial intelligence that could both replace them in these difficult tasks, but also take responsibility for many other tasks within the complex and compete with Black Mesa's superiority. All employees of the Aperture Science complex are now eagerly awaiting GlaDOS. Maybe even a little too eagerly, as the upcoming events will tell...