Peer Review Logo

After a routine experiment goes catastrophically wrong, Dr. Gina Cross and Dr. Colette Green must fight to survive the aftermath of the Black Mesa Incident.

Peer Review is a reimagining of Half-Life's third and final expansion, Half-Life: Decay. Return to the Black Mesa Research Facility and relive the chaos from the perspectives of Dr. Cross and Dr. Green. With all missions from the original game and fully functional co-op, Peer Review aims to give a fresh take on classic Half-Life that you can enjoy with a friend.

Peer Review and PSR Digital have no affiliation with Valve Software, Crowbar Collective, or Tripmine Studios.
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Hello everyone. We have lots of good news, and a bit of bad news.

Bad news first: I am sorry to announce that, unfortunately, our Source 2 license has been revoked in the ~72 hours since we posted our last update. Turns out that there are a bunch of thorny legal issues with using Source 2 for our project (such as, y'know, the fact that the Source 2 SDK doesn't actually exist yet...), which means we're just gonna have to suck it up like all the other modder plebs out there and stick with Source 1. Sucks to be us, I guess. Boooo.

ANYWAY, now that we’ve gotten the industry-mandated April Fools’ Day shenanigans out of our system, we at PSR would like to offer you guys a bit of a consolation update in light of the aforementioned disappointing news. So, we'd like to show you a tiny slice of what we've actually been working on over these past few months. In short: we've been hard at work on team-building and laying down a solid foundation to base the rest of the game on. Unfortunately this means there's still a while to go before the next major news update with lots of pretty art and media, but there’s still some exciting stuff happening behind the scenes! Here's a quick sneak peek at what we're currently working on.

Character Design

First up is an important detail for our player character models: updated heads! Check out this lovely 3D render of a certain Dr. Colette Green’s fair visage:

A particularly hairless Dr. Colette Green

Some of you keenly noticed that in our reveal video from last December, Dr. Green was sporting the head of a female citizen character model from Half-Life 2, bearing absolutely no resemblance to her actual appearance in Half-Life: Decay. Worry no longer! Thanks to our lead character artist, Michael Tannock, Colette will soon have an actual face in Peer Review. (And yes, we are aware that she currently has no hair... that’s the nature of a mid-development update.) Here's some concept art (also courtesy of Michael Tannock) of what we envision her actual complete head to look like, once the model is more fleshed-out:

A painted Dr. Colette Green, with hair

3D Art Department

To follow that up with a bit of a twist, we’d actually like to give something back to the modding community in one of these updates. As it turns out, our branch of the Source engine (2013 Multiplayer) actually includes support for lightmapped static props, which means improved lighting across the board for what we plan to be much more heavily mesh-based levels. Our very own JifMOD has slaved away many hours in front of a keyboard to figure out the quirks of this heavily undocumented feature of Source, so that you don't have to. He wrote up his findings on how to add lightmaps to YOUR props if you're using the 2013 Multiplayer branch of Source, in the form of a quick mini-tutorial here:

JifMOD Writes:

In the process of updating one of our models to support lightmaps, I noticed that while VRAD was packing lightmaps into all the static props in my test map, only the HL2 model I was using as a control test was actually displaying them. After decompiling the model and comparing the .qc files (scripts that define the visual and physical attributes of a model) there weren't any major differences between the two aside from what source .smd files they were pulling the model data from. This led me to a long process of commenting out material code and retesting the map, which led me to discover some undocumented limitations in the material system. If you're working in Source and want fancy lighting on your models, keep the following in mind...

(Read the full tutorial here:

Thanks Jif! Although I’m sure a lot of that technical stuff probably sailed over a lot of you guys’ collective heads, we hope that the above information might be useful to anyone who might be a Source modder (or an aspiring Source modder) who’s in a similar situation that we were in just a few weeks ago when we were figuring all this stuff out.

Sound Design and Music

On the audio front, we're pleased to announce that we have a new member joining the team! Jupiter will be joining us as a composer for Peer Review, and he's already helped us come up with some really neat ideas for how to make our game music a bit more fleshed-out. In particular, we've come up with and implemented a new dynamic music system that will allow our level designers to smoothly transition in and out of various musical tracks in response to in-game events, or even script in-game events to trigger when a particularly sweet beat drops!

While dynamic music might seem more suited to the action-adventure genre, we’ve got plenty of ideas up our sleeves for how to best utilize this new hammer in our toolbox. And if you'd like to see a (very rough and early) demo of the system in action, check out this internal development video we recorded some time ago:


As I mentioned before, a lot of our work over the past few months has been focused on team-building. We’ve been sourcing talent from across the community to see if we can find some extra sets of hands to help this small team of ours build this hugely ambitious project, and while we do have several promising candidates in the recruitment pipeline, we’re nowhere near our recruitment target for the project yet.

If you have useful skills and might be interested in helping out with the project, please send in an application at our application form here! Or even if you don’t think you’d be able to help out, but you know someone who might, definitely send them our way! We’re looking for people to fill just about every role in game development, from level designers to animators to sound designers. Head on over to our ModDB Jobs page and see if there might be a good role on our team for you or anyone you know. Or even if you don’t, all we ask is that you spread the word that we’re recruiting!

… and that about does it for today! Although admittedly this update was a little sparse, that’s mostly because it's still early, and we’re working steadily behind the scenes to build a solid foundation for this game that can support the weight of our vision for the project. This, of course, necessarily involves experimenting with lots of ugly in-development stuff that isn’t ready for public prime time just yet. There are still lots of cool things that we currently have planned or in the testing and iteration stages, and I can’t wait to show them off once they’re ready.

Until next time!


Beware the Ends of March...

Beware the Ends of March...

News 6 comments

We've got some exciting news for you all! You may have noticed we've been eerily silent since first announcing the mod - that time has been well spent...

Announcing PSR Digital's Next Project...

Announcing PSR Digital's Next Project...

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At long last, after years in pre-production, we're finally able to show you guys what we've been quietly working on in the shadows. Here it is-- a small...

Source 2013 Lightmap Documentation

Source 2013 Lightmap Documentation

Props Modelling Tutorial 1 comment

A quick summary of the undocumented limitations of the lightmap system present in Source 2013 and TF2 Branch which may prevent lightmaps from rendering

Comments  (0 - 10 of 104)

Will you keep that awesome retinal scanner model from decay?

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dky.tehkingd.u Creator

The retinal scanner is actually one of the models that we haven't made yet. So we can't really say for the moment.

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This looks promising though Hl:decay remakes have come and gone before. Do you intent to remake all the levels from the game including the ones that got cut from the original game? Do you hope to get this on steam like Black Mesa has and other remakes like Guard Duty/Operation Black Mesa plan to do?

Do you have a website, forum, or discord for this mod?

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dky.tehkingd.u Creator

It's still very early, so we don't currently have anything specific that we're able to share about the story or missions that we currently have planned for the project. Suffice it to say though, that we definitely aren't planning to make a carbon copy of the original.

We do hope to get this on Steam, but there's still a ways to go before that can be put on the table. For now, we're focusing on making the game rather than jumping the gun on a distribution plan before we're ready for it.

No forum or Discord server as of yet, but we will set up a Discord server once we feel we have enough publicly-shown content worth discussing!

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Ok :)

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I really really REALLY hope you guys succeed, Decay is vastly underrated IMHO and bringing it back to spotlight with a proper remake would be godly. I really wish I could help if I wasn't already drowning in mod work, but fingers crossed you'll find dedicated and talented people soon ;)

Good luck and can't wait for the game!

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Hi everybody! Just a simple question for the developers of this fantastic mod. There is any plane to include in the mod the cut missions of Decay's storyline such as The Hub and The Hangar? Thanks and good luck!

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dky.tehkingd.u Creator

It's still very early, so we don't currently have anything specific that we're able to share about the story that we currently have planned for the project. But I can at least say that we don't plan to make our version a carbon copy of the original!

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Do you have any intentions of putting this onto steam?

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Crypt CreatorSubscriber

It's definitely something we'd like to do and are looking into! There's some hoops to jump through first but it's very much on the list.

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