Portal: Prelude is an unofficial prequel to the game Portal. 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. The v1.0.0 is now locally mirrored at gamershell.com.

What do i need to be able to play Portal: Prelude?

In order to play Portal: Prelude you need to have Steam installed on your system, of course. You also need to be the owner of Portal and probably nothing else. Half-Life 2, Counter-Strike Source, Day of Defeat Source or the Source SDK Base (which can be downloaded for free in the tools tab of Steam) may be of some use, but we don't think so. In fact, I'm not really sure you need anything else than Portal.

Portal: Prelude Homepage