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  (340 - 350 of 376)
sathanas Oct 10 2008 says:

For anyone who does not consider themselves a hardcore Portal player / speedrunner, just avoid this.

The first chamber gave me a bit of a laugh after warning me not to do stupid things with portals, and then jumping into the middle of several turrets, but after that there's really no appeal.

The story you pretty much know from what GLaDOS says during Portal, so much of the appeal of being "more than a map-pack" is lost straight away.

Perhaps it's good in French, but as someone playing through on English, the translation and voice synth programs used to create the voices just ruins any sort of atmosphere. It's like playing through with a schizophrenic GLaDOS most the time. Which would have been a cool thing if it was during the start of her meltdown, but... sadly I don't think it's intended.

Where Portal threw some challenges at you, generally it would take just a few attempts to figure something out. Rooms were clean and guided your eye to the solution to most chambers. Portal: Prelude does away with any sort of user friendliness, and even at one point makes a joke of the solution to puzzles making no logical sense. "Did you see that part of the wall I moved. It was of no use. A ha ha ha ha," that's pretty damn hilarious, you zaney frenchmen! Watch as I hold my sides to stop them from splitting.

The test chambers, from the very start, require near perfect timing and a lot of trial and error. If you enjoy repetitive pain, this will be right up your alley. Go ahead hardcore minority, tell me I'm missing the point. It's supposed to be hardcore to the max! I'm just warning the average player that they'll probably end up burning this to a dvd just so they can put it through a shredder.

3/10 for me, someone who found Portal enjoyable as it was and felt no real need to challenge myself further. If the story was any way decent or even unpredictable, it might get as high as 5 even with the state of the test chambers.

+4 votes     reply to comment
Bubbinska Oct 10 2008 replied:

I'd like to second Sathanas' remarks. I'm up to chamber 19 and while the puzzles have been fairly clever and I appreciate the effort made in producing more challenging puzzles, what severs my enjoyment of the game is the use of unintuitive, precision portalling as a means to solve the puzzles.

What made Portal's puzzles enjoyable was that the time limits, if any, were fairly lax, so you had room to carefully plant your portals. Chamber 18, where I need to press a button, make an infinite loop and launch myself, then quickly jump from button to button to solve the rest of the problems was just plain painful. It's not that I couldn't figure it out, it's just that the sluggish view-rolling and confusion from portalling yourself into a daze makes it difficult for me to accurately and easily solve the puzzle. I finished it but not after swearing up a storm at the crazy requirements. There are other issues in other Chambers but I don't need to explain them all.

The problem is that these puzzles are designed for a lightning-fast, smooth and intuitive engine, while Portal is sluggish and clunky in this situation. It's like a ham-handed sumo wrestler trying to thread needles.

I'm really impressed at the effort put into this mod, and while the english voice "acting" is a bit odd, and has dodgy grammar, it's still pretty good. My issue is with the puzzles - They are easy to find the solution to, but hard to execute that solution. It should be the other way around.

+7 votes     reply to comment
sudoku424 Oct 10 2008 replied:

what helps is when you're not running it on minimum requirements.

+2 votes     reply to comment
feltorn Oct 9 2008 says:

should this mod be taking over 10 hours to download?

+1 vote     reply to comment
Guest Mar 17 2013 replied:

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sudoku424 Oct 10 2008 replied:

that depends on how your connection is. it's .75GB

+1 vote     reply to comment
FRIGGIN-KYLE700 Oct 9 2008 says:

Wow, very nice mod/game. Although, I would recomend a patch that fixes/redoes the voice acting.
But very nice work, it's very hard and challenging.

+1 vote     reply to comment
KILLER89(FIN) Oct 9 2008 says:

Just finished the mod.

What can i say...

It's not a mod, it's a ************* master piece of art.

+1 vote     reply to comment
BadCoupon Oct 8 2008 says:

It's out on Fileplanet (which sucks in my opinion).

+3 votes     reply to comment
zahlenbechk Oct 9 2008 replied:

Released on fileshack now.

+1 vote     reply to comment
PhillInHoles Oct 9 2008 replied:

Would be nice to have a moddb mirror.

+3 votes     reply to comment
iMoo Oct 8 2008 says:

YES YES YES 2 more days

+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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