You are Barney Calhoun, a security guard at the Black Mesa Research Facility. Unknowingly to you, the next few hours of your shift will change your life forever...
Re-live the exciting adventure of Blue Shift on the award winning Source Engine and prepare for the shift of your life!
Welcome to Guard Duty.


- As a total conversion mod, Guard Duty aims to be composed of entirely custom content
- All original maps re-created and re-envisioned for better realism and gameplay.
- Some maps are enlarge/extended to create a more lengthy and immersive game.
- Improved AI, making enemies smarter and even more dangerous than ever before.
- More enemy encounters to keep the action fresh.
- Scripted scenes with all the original Blue Shift characters to help bring the story to life.
- Textures and models that will push the limit of the Source Engine, to bring you as much artistic detail as possible.
- All new voices, sounds and music.
- Multiplayer, which may (or may not) contain various game modes.

And much more!

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Living quarters outbound Hazard Course Concepts
Blog RSS Feed Report abuse Latest News: 2014 Kickoff Update

22 comments by Uphys on Mar 29th, 2014

Welcome to our first media update this year!

Read Full Article.

Multiplayer Beta Release Q1 2014 Cancelled

Our plan to bring you the multiplayer beta of Operation Black Mesa early this year didn't work out, regrettably. Several factors and circumstances forced us to completely keep it under the hood until further notice.

Multiplayer Progress

Multiplayer will feature classic maps such as Yard, Crossfire and Boot Camp as well as brand-new ones like Deptcharge and Gambit from day 1.
Currently in development: CTF mode and weapon placement.


Singleplayer Campaign

Development is running smoothly; those NPCs aren't going to animate themselves though! If you're interested in joining our team, check out the jobs page where you can find all positions currently open. We look forward to welcoming you on board!

Pit Worm's Nest

Remember Guard Duty (Blue Shift: Source)? We're making solid progress here too:

Living Quarters Outbound

OBM: The Video Game?

We've been given the option of developing our projects as full indie titles to be sold on Steam!
This opens up a whole lot of attractive possibilities to consider; however no decision has been reached yet as to this matter.

Alien Controller

M1A1 Tank

Thanks for your support in making all of this possible!

Until next time,
Tripmine Dev Team

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Elevator to hell

Elevator to hell

Jun 15, 2011 Music 4 comments

An example from our soundtrack. This track is made by "Becket007".



Jun 15, 2011 Music 2 comments

An example of Xen track. This track is created by 8BitLord.

Sigh of relief

Sigh of relief

Oct 16, 2009 Music 6 comments

An example from our soundtrack. This track is made by "Mordekai"

Post comment Comments  (70 - 80 of 1,434)
TheSleepingObama Mar 7 2014, 1:43pm says:

Who was the guy in the AI presentation?

-1 votes     reply to comment
afterwars Mar 19 2014, 11:20am replied:

The guy filming, or the guy talking?

+4 votes     reply to comment
TheSleepingObama Mar 5 2014, 1:46pm buried:


I don't agree with sharing content with your projects. We all love to see different things for each mod.

It adds diversity to see what people want to make things look. But hey i'm fine with it, it's just be cool to see other peoples spin on it then having the same mod in a way.

-6 votes     reply to comment
Crypt Mar 22 2014, 6:48pm replied:

I like how following this logic leads to HL, BS, Op4, Decay, and hundreds of GoldSrc mods all being the same game.

+4 votes     reply to comment
Guest Mar 2 2014, 1:35am says:

How come Operation: Black Mesa is for Mac and Linux but not this? I'm curious.

+3 votes     reply to comment
JohnSmirnov Jan 17 2014, 8:45am says:

Are you going to post it on Steam Greenlight?

+1 vote     reply to comment
MR.sugar Creator
MR.sugar Jan 17 2014, 6:25pm replied:

No plans to do it so far, mainly because Greenlight will shut down soon.

+2 votes   reply to comment
Ragnar_Lothbrok Jan 18 2014, 2:58pm replied:

Ok Evilgoodguy I understand :) and who the f*ck the downvote?!

+2 votes     reply to comment
JohnSmirnov Jan 17 2014, 8:20pm replied:

I have seen El Oschcuro posts on Twitter, but dont worry, they didnt said they will do it immediatley, they just PLAN to take Greenlight down, to make games appear on Steam easier. But its not known what they will replace Greenlight with, when/if they will take it down.

+1 vote     reply to comment
Ragnar_Lothbrok Jan 17 2014, 6:56pm replied:

F*cking Valve, this will bring worse consequences for OBM? :(

+1 vote     reply to comment
JohnSmirnov Jan 17 2014, 7:55pm replied:

Gabe didnt said that, El Oshcuro is the one who said it on Twitter (reblogged from SteamDevSats). But they said they will make the easier and better way to games appear on Steam if/when they will get rid of Greenlight.

+1 vote     reply to comment
EvilGoodGuy Jan 18 2014, 7:24am replied:

I attended Steam Dev Days, so I can confirm that indeed it was announced (by Gabe) that Valve is looking at getting away from Greenlight; and honestly I can totally see why. I don't blame them and I don't think its a bad thing either. I'm sure there will be other ways for mods to be easily accessed/distributed across steam in the future. Valve aims to give the fans what they want or like the most. So its inevitable. And no, PFaustBC, this will not affect OBM at all :)

+3 votes     reply to comment
JohnSmirnov Jan 18 2014, 9:17pm replied:

Thats what I said and whate Dave Oshry confirmed, they want to change it to a better system or something like that. Buts its very arguable question too, Greenlight allows people to chose what projects and games they want to appear on Steam. While considering Gabe's logic, that new system would allow to put absolutely everything much easier, so this will allow very bad projects and games appear on steam, or a lot of unfinished projects people will pay for etc. Here is the problem. Btw, not only mods, games and various other stuff too :P

+1 vote     reply to comment
JohnSmirnov Jan 17 2014, 8:05pm replied: +1 vote     reply to comment
MR.sugar Creator
MR.sugar Jan 18 2014, 3:51am replied:

Yea, though it's still unclear what exactly will happen. Our team, in terms of PR, is focusing on OBM more right now and Guard Duty is being developed behind the curtain. And so far, it looks like we are never going to post it to Greenlight (or any kind of future Steam-approval process).

+2 votes   reply to comment
JohnSmirnov Jan 18 2014, 9:19pm replied:

Why? You mean you may never finish it?

+1 vote     reply to comment
Crypt Jan 19 2014, 2:38pm replied:

It will be finished, there's just no plans to put it through Greenlight as Valve has expressed interest in shutting down Greenlight.

+1 vote     reply to comment
JohnSmirnov Jan 21 2014, 9:25am replied:

But they didnt said that they WILL shut down and didnt said WHEN they will shut down it. And if not Greenlight, why not on the new system that they will make instead of it?

+1 vote     reply to comment
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