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

21 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
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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  (60 - 70 of 1,405)
FritzOfTheSS Nov 25 2013, 1:43am says:

When you guys say custom content, do you mean shares between both OBM and GD, or exclusively all new custom content for both, being completely seperate.

The AI for Soldiers in OBM will be vastly different than in GD.


No models will be the same in both games, and both will be completely different.

0 votes     reply to comment
EvilGoodGuy Nov 26 2013, 12:44pm replied:

By "custom content", we mean that it is made by us, and not borrowed from another project or team. The content in OBM and GD will be shared/the same. We are just 1 team making 2 projects, so it would be a waste of time and also break consistency to make the content different.

+4 votes     reply to comment
Guest Dec 1 2013, 3:49pm replied:

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MR.sugar Creator
MR.sugar Dec 1 2013, 4:55pm replied:

Nothing like that. I believe BM team is more than cappable of fixing them on their own ;)

+1 vote   reply to comment
Guest Nov 23 2013, 3:26am says:

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TheSleepingObama Nov 12 2013, 1:40pm says:

Let me ask you something, is it hard to not base your work off "Black mesa: Source"?

-2 votes     reply to comment
OJJ0874 Dec 11 2013, 1:31pm replied:

Let me ask the Black mesa: Source team is it hard not to base your work off "half life"

-1 votes     reply to comment
afterwars Nov 13 2013, 5:12pm replied:

Not really, as the general areas of the levels in the Mods differ greatly in style, and it's better to get a sense of pride of doing your own work instead of copying off of others. However, indubitably, some details will be copied from mod to mod, due to the general increase in quality from the original, to the remake mod. E.g. Similar-ish Laboratory equipment.

+2 votes     reply to comment
TheSleepingObama Nov 18 2013, 1:33pm replied:

Oh cool. Yeah me and the BMR team are working on general look for most areas and such.

-2 votes     reply to comment
capomaster Dec 13 2013, 6:41am replied:

Hey sleeping obama,
you didn have you own proyect called The Shift?
Sorry for my horrible english

+1 vote     reply to comment
TheSleepingObama Mar 5 2014, 1:44pm replied:

I do not believe so. Why do you ask?

+1 vote     reply to comment
papatub154 Oct 21 2013, 2:32am buried:


is there any way we can have the hands? like a demo maybe just to replace the default gordon hands in Black Mesa. i LOVE black Mesa but i dont wanna be a scientist anymore.

-7 votes     reply to comment
Crypt Oct 24 2013, 10:34pm replied:

What is up with people asking unreleased mods for their assets? I don't get it.

+5 votes     reply to comment
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