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

23 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  (60 - 70 of 1,438)
Guest Jul 21 2014, 2:55am says:

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MR.sugar Creator
MR.sugar Jul 26 2014, 6:01am replied:

Maybe, there is one thing we plan to implement from the early builds of Blue shift, but it will also be optional.

+1 vote   reply to comment
werdman2 Jul 10 2014, 4:30pm buried:


why is has the bull squid being redesigned can you not directly use the assets from black mesa source? or is it because the image was released before black mesa was released?

-5 votes     reply to comment
CommanderBox Jul 12 2014, 12:41pm replied:

have you ever heard of the word called "stealing"?

+4 votes     reply to comment
radiation_hazard Jun 2 2014, 6:54pm says:

Would you consider letting the player explore Barney's dorm before entering the tram?

+6 votes     reply to comment
MR.sugar Creator
MR.sugar Jun 16 2014, 9:26am replied:

While it sounds awesome, it would be a lot of extra work for something that has no real positive impact on the game. The introduction is already long enough, if we make it any longer, game would suffer. Not good especialy for repeated playthroughs.

+3 votes   reply to comment
radiation_hazard Jun 18 2014, 5:11am replied:

Then I suppose I'll just use noclip to get a longer look the second time I play.

+3 votes     reply to comment
NightHawk107 Jun 2 2014, 10:03am says:

will this be release in 2015?

-4 votes     reply to comment
austinzolo Apr 23 2014, 7:18pm says:

So this mod will include it's own version of Uplink? does that mean you get to play as Freeman with the HWV?

+2 votes     reply to comment
austinzolo May 2 2014, 8:20pm replied:

I mean "HEV"

+1 vote     reply to comment
MR.sugar Creator
MR.sugar May 5 2014, 9:37am replied:

We will reveal more about Uplink at some point. While the main point will be the same, we aim to intergrate the storyline better to the story and make it cannon, at least in terms of our universum. This may bring some changes you wouldn't expect. But later about this

+4 votes   reply to comment
austinzolo May 5 2014, 9:06pm replied:

Okay cool

+3 votes     reply to comment
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