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!

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

20 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

Media RSS Feed Latest Audio
Downloads RSS Feed Latest Downloads
Elevator to hell

Elevator to hell

Jun 15, 2011 Music 1 comment

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 1,395)
KCKI113R Aug 8 2013, 2:14pm says:

Hey guys, will you add Kleiner, Eli and Magnusson to the later chapters of Guard Duty? I'm glad Black Mesa did that, but will your team do that? (BM failed with Magnusson, he was supposed to be included, plus if you add them it will add a sense of continuity between the Half Life games and it will allow you to extend the ending sequence by making 1 more person go through (more enemy encounters could also be added there))

+2 votes     reply to comment
Crypt Aug 9 2013, 12:28am replied:

When do Kleiner, Eli and Magnusson make an appearance in Blue Shift?

Also, BM didn't fail with that, Magnusson was never confirmed as having made an appearance.

+2 votes     reply to comment
[MC]Pimpão Jul 17 2013, 8:49pm says:

i might sound pretty ignorant... but i wanted to ask why isn't this mod on greenlight since OBM already is.

+2 votes     reply to comment
EvilGoodGuy Jul 18 2013, 12:22am replied:

Thats a perfectly acceptable question :P
A release date is required for greenlight. So we set a estimated release date for the first version of OBM multiplayer. GD does not yet have a estimated release date.

+6 votes     reply to comment
PoGo142 Jul 8 2013, 3:17am says:

In the original Half Life there was a consistency error that shows Barney with his full gear knocking on the door while in Blue Shift Barney was unequipped on the door.
Are you going to do something about that?
^ Not referring about Black Mesa

-1 votes     reply to comment
EvilGoodGuy Jul 9 2013, 12:40am replied:

Considering you play as Barney in Blue Shift, and the game is a First Person Shooter, there is nothing to fix :P So you will be pleased to know that just as in the original Blue Shift, the player will not get his equipment until the locker room.

+1 vote     reply to comment
Humin Jul 13 2013, 8:45pm replied:

Are you implying that barney wears 2 sets of armor?

-3 votes     reply to comment
EvilGoodGuy Jul 14 2013, 2:36pm replied:

I'm implying that in Guard Duty, the player (Barney) does not get his armor until he picks it up from his locker.
So I'm implying he has only 1 set or armor and that Blue Shift was made after Half-Life was :P
Since we are remaking Blue Shift, there is nothing for us to fix.

+2 votes     reply to comment
Humin Jul 16 2013, 7:11pm replied:

Well, he's still wearing the vest in half-life before he's supposed to get it.,

-3 votes     reply to comment
EvilGoodGuy Jul 16 2013, 7:43pm replied:

What I'm saying is, Half-Life 1 is completely irrelevant. The story of Blue Shift wasn't even thought of, or even developed by Valve at the time Half-Life 1 was made. It was developed AFTER by Gearbox software. So of course he is wearing the vest in HL1... he had no reason not to be, since blue shift wasnt even thought of yet.
Hell, the character, Barney, wasn't even a character at the time. He was just a generic security guard seen a thousand times. So after understanding that time travels in a linear motion, and that HL1 came before Blue Shift - There is nothing we can/are going to do about this.

+5 votes     reply to comment
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