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

25 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  (1200 - 1210 of 1,447)
Jamie240 Jan 12 2008, 8:07pm says:

This mod is going to kill me I will watch it day and night

+2 votes     reply to comment
Kub Jan 10 2008, 2:15pm says:

No, of course not. We were just planning to add some plot curves. Don't worry, nothing of the original is going to be spoiled .

+1 vote     reply to comment
cobo10201 Jan 10 2008, 10:39am says:

ok i was just readin the description and it says "Rather than in the original Blue Shift the storyline is presented in another view" wat does tht mean? we rnt playin as barney?

+1 vote     reply to comment
syb123456 Jan 9 2008, 6:27am says:

Did some who know that produces the date!

+1 vote     reply to comment
dethtoll Jan 8 2008, 4:47pm says:

As awesome as this mod is, I hope you give us the option to use HECU troops, to be true to the original game.

+2 votes     reply to comment
ThaWall Jan 5 2008, 4:31pm says:

This mod is looking good!

+4 votes     reply to comment
MR.sugar Creator
MR.sugar Jan 6 2008, 3:35am replied:

Yeah looks great. I really cant wait for media update.

+2 votes   reply to comment
norton2 Jan 4 2008, 7:44am says:

Oh noes I posted a swear sword and got 71% negative influence :(

+3 votes     reply to comment
phipe Jan 4 2008, 9:27am replied:


+1 vote     reply to comment
diegovb Jan 5 2008, 4:28pm replied:


0 votes     reply to comment
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Guard Duty
Guard Duty
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9 months ago
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