Why ?
In January 2008, I was searching for a new project. Portal was out since four months, and still, no-one had already did something really serious around it. I was following a lot a communities, seeing a lot of independant releases, but no mod and no serious story arc. This I why I decided to launch this project.

How ?
At start, the project was rather insignificant. It was not supposed to be a mod (modification of a game), but just a succession of test chambers, without any real logic between each of them. I had no goal, I was just making maps as I saw it. And finally, when I reached a dozen of test chambers, I realized that I would be a shame to waste all my work by only releasing yet another map pack without any real story. This is where I began to write a whole new story and decided to follow the famous belief that prequels are somewhat popular recently.

What ?
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, 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...

Who ?
My goal was to make it a personnal project, without telling anyone about it. I wanted to surprise everyone by releasing a quality, polished and fully finished game, offering roughly the same amount of playtime than Portal. As months passed, I had more and more difficulties to keep working regularly on it. In real life, I'm both a student and an employee, and that didn't left me a lot of time to work on the game. This is where I decided to ask for some help, mainly from Jérémy "Capitaine Mousse" Barbe, who helped me by making four of the nineteen test chambers while I was working on the final level. Marc "Moroes" Bidoul helped me too, by making a few 3D models and textures.

How long ?
Eight months. Not eight month of continuous work of course, but eight month with some days filled with dozens of hours of hard work. I worked on the nineteen test chambers for 3 to 4 months, followed by 2 months on the final level, and 2 months of tests, debug, and polishing (interfaces, voices, commentaries, etc.). I must confess that it took me a lot more time than I initially thought, mainly because I had exams and work to do on behalf.

And after ?
In June 2008, I learned as everyone else that Valve was working on an official prequel of Portal. I must say that I was mostly the only guy on Earth not really happy by this announce. So, I decided to work twice as hard to release my version way before Valve's one. I hope that they will not take it too personnally, because mine was in development 5 months before their announcement.

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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  (50 - 60 of 375)
Guest Mar 16 2013 says:

If you can't see the particles of the Emancipation grills in this mod, then this is for you: To fix the particle problem of the fizzlers, you need to go to your "steamapps" folder then "scourcemods" then "portalprelude" folder then go to particles and delete "prelude_cleansers". Then go to your original portal folder go to particles and right ckick on "cleanser" copy it, then go back to your "portalprelude" folder then particles folder and paste it. Then rename the pasted file to prelude_cleansers. then load up the game and you should see the particles.

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Guest Jan 19 2013 says:

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shadow09c Jan 24 2013 replied:

You may be missing some textures and other things, try getting HL2 installed and run it one time before running the mod again.

0 votes     reply to comment
regularshowman Jan 7 2013 says:

An incredible experience, haven't even beaten it yet!

+1 vote     reply to comment
Paper_Guy Sep 28 2012 says:

I got this mod a while back, and I thought I installed everything correctly. I loaded the game, and saw purple and black checkerboards everywhere. Also, there were 3D models that said "ERROR" in place of a lot of things. How do I fix this?

+1 vote     reply to comment
Guest Mar 14 2013 replied:

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isavegas Oct 17 2012 replied:

It has a major issue with the "trailor.bik" file in the media folder. You have to make a Portal Prelude folder manually and extract everything but "media" into it, then make a media folder and copy everything but trailor.bik into it from the media folder in the archive.

+1 vote     reply to comment
turbosquid Sep 11 2012 says:

Hey, guys. I downloaded a torrent for portal and it worked and everything. I also downloaded some mods including this one but everytime i launch it, it just takes me to the steam screen? Does anybody know how I can fix this? Thanks:)

+2 votes     reply to comment
isavegas Oct 17 2012 replied:

1. You can simply make a copy of the entire portal folder in the folder you installed it in and rename it portalprelude, then copy all of the items from the portal prelude zip (except the media folder) into the new folder, overwriting if neccesary, then make a new shortcut leading to the hl2.exe file where you installed portal, making sure it is in quotes, then add " -game portalprelude" to the end of it, OUTSIDE OF QUOTES. It should look like this--- "C:\InstallLocationOfPortal\hl2.exe" -game portalprelude
Once you do that, you can move the shortcut to your desktop or to your start menu, and launch it from there. It will load up the game and say "Portal: Prelude" instead of "Portal" in the main menu. Done!
2. Buy the game and just download the zip, then extract it to C:\Program Files (x86)\Steam\SteamApps\sourcemods and restart steam, then launch it from the games library.

+1 vote     reply to comment
D1orTwo Sep 21 2012 replied:

Yeah, buy the game... Don't be a pirate. Support the devs, you wouldn't expect to go to work and not get paid right? Why should they work for you for free..?

+1 vote     reply to comment
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Release date
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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