Portal: Prelude, as its name states it, 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, and 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... This game is totally free. It offers a bit more gameplay hours than the original Portal, with 8 chapters, 19 test chambers, 48 challenges, 6 advanced maps, a brand new storyline and more than 400 lines of english speech with dozens of subtitles translations. Read More...

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Every vote counts and may win you a game on Steam!

Ok, that's right, it's a kind of big surprise. After 114,000 votes, Portal: Prelude didn't win the ModDB's Mod of the Year Awards, but made it to the third place! Surprinsigly enough, we also managed to beat the most acclaimed mods of 2008, including nearly every mod that got into Steam during the year.

  1. Project Reality (Battlefield 2)
  2. Zombie Panic: Source (Half-Life 2)
  3. Portal: Prelude (Portal)
  4. First Strike (Battlefield 2142)
  5. Zombie Master (Half-Life 2)
  6. Pirates, Vikings and Knights 2 (Half-Life 2)
  7. Eternal Silence (Half-Life 2)
  8. Age of Chivalry (Half-Life 2)
  9. Stargate Empire at War (Starwars Empire at War)
  10. Half-Life 2: Wars (Half-Life 2)

I must say that I'm really happy with the results, it's kind of the best place ever for a little mod like ours that grew up rapidly from nowhere with a really small team but a really big motivation. It wouldn't have been fair to finish first or second regarding the amount of work and devotion put into some of the mods out there. Some of them who recreate everything from scratch and build something during years with sometimes hundreds of people. That's why I'm happy to be third!

I must say that our little team is quite proud of this result! After all, it proves that even if we crossed a terrific jungle of insults, harsh criticism and mockery, we managed to please the people at which this mod was first aimed: all-time Portal fans, hardcore challenge-looking players and a few of them who thought Portal: Prelude was cool enough to buy Portal once and for all (no joke here, I could cite you some e-mails I received).

Thanks to all our fans, to all the people who helped us and tried to help us in any way (e-mails, voices, forums, scores, bugfix, etc.), and thanks to all the people who sent us feedback via e-mails, comments, discussion boards or our forums. Thanks for the hundreds (maybe thousands) of e-mails to tell us your experience, your disappointements and your best moments. We couldn't reply to everyone (even if I tried to reply to at least 70-80% of them), but I can assure you we read everything.

Check our "meet the team" page to see all the people who really helped us.

Portal: Prelude 1.1.5 released!

Portal: Prelude 1.1.5 released!

6 years ago News 13 comments

This new version is shipped with more than 115 bug fixes, improvements and additions (since 1.0.0). We know everything's still not perfect, but we believe...

Portal: Prelude 1.1.0 released!

Portal: Prelude 1.1.0 released!

7 years ago News 29 comments

Portal: Prelude 1.1.0 released! This new version is shipped with more than 80 bug fixes and additions, along with slightly easier first levels.

Portal: Prelude Released!

Portal: Prelude Released!

7 years ago News 26 comments

That's it! Portal: Prelude is released! Thanks to FilePlanet and Planet Half-Life, you can now download the game one day before the official release date...

Day One : The Trailer

Day One : The Trailer

7 years ago News 26 comments

Here we are, Day One. The trailer is up and running.

Portal: Prelude 1.1.5 (archive version)

Portal: Prelude 1.1.5 (archive version)

5 years ago Full Version 30 comments

All the files needed to make Portal: Prelude run. This version is exactly the same than the "installer" version except that it works better for Mac OS...

Portal: Prelude 1.1.5 (complete installer)

Portal: Prelude 1.1.5 (complete installer)

6 years ago Full Version 102 comments

This new version is shipped with more than 115 bug fixes, improvements and additions (since 1.0.0). We know everything's still not perfect, but we believe...

Post comment Comments  (320 - 330 of 375)
scorpionus Oct 16 2008 says:

This mode is AWSOME!!!!!
I like it.......
Greate puzzels and battles...
you should make Portal Prelude 2 like Valve makes Portal 2

+1 vote     reply to comment
Toblerone Oct 14 2008 says:

Great fun, good puzzles, and indeed challenging. I've not yet completed it. I'm on 18/19 now which is gettin a little frustrating, cant wait to see the end :)

+1 vote     reply to comment
droot Oct 13 2008 says:

some levels are indeed challenging but for the most part I find them more frustrating than enjoyable. Hey.. But it's only my opinion

+3 votes     reply to comment
skarai Oct 12 2008 says:

Voice acting pretty much ruined everything.

+3 votes     reply to comment
NykO18 Creator
NykO18 Nov 5 2008 replied:

Next time we'll do it with text only, or in french.

+1 vote   reply to comment
Fireyone Oct 15 2008 replied:

I find his Voice Acting (WHICH WAS A MICROSOFT SAM/WHOEVER) actually helped the game feel like Portal.

+1 vote     reply to comment
norton2 Oct 14 2008 replied:

don't be so mean.

+1 vote     reply to comment
Floodkiller Oct 12 2008 says:

Great pack so far, i'm up to room 9.

Which reminds me, are you crediting Portal: The Flash Version (not the map pack MADE by those guys, but the actual Flash version) for inspiration for your levels? Because some of your levels are very reminescent of them (the eletric area, the 3 crusher sprint, etc.).

-1 votes     reply to comment
Ulver Oct 11 2008 says:

Kind of a great mod. But the last levels had a few backtracking-problems, and the boss-fight sucked. Death/survival was completely arbitrary, and in the ending scene a counter appeared on all the screens without any context to the boss fight (e.g. no counter started, no gassing everyone started etc).
This mod definately needs work, but it has got potential :)

+1 vote     reply to comment
turkey72 Oct 11 2008 says:

oh and nyk018 may i please use your: citizen skins,manhack skin and sound and upload it fpsbanana?

+1 vote     reply to comment
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Released 2008
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688 votes submitted.

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Highest Rated (5 agree) 7/10

It must be admitted that if you take nothing else from this mod, its sheer scale is quite exceptional. With new characters, voicework, puzzles and approximately double the length of the original portal (not to mention its difficulty in places) it is hard to den the dedication and hard work that has gone into this mod. The storyline is fairly solid – although I expected the malice of on of the observers to continue – which is impressive and a testament to what can happen if a mod team sit down…

Nov 5 2010 by newnowmusic

Lowest Rated (7 agree) 3/10

If I were to give Portal: Prelude any credit, I'd say it was very ambitious, and I'd congratulate the developer for finishing it. However, the mod is not entertaining. It has terrible voice acting for one, because the creator himself admitted he could not be bothered to find actual people. In addition to terrible voice acting, the characters that need the voices are all very badly written. They have an unecessary amount of malice for the player; while that was funny in Portal, it lacks any semblance…

Jan 17 2011 by Darkurai

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