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

16 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 1,388)
therupertbob Jun 2 2013, 4:03am says:

Will Guard Duty use the new North Level 3 Dormitories Entrance from Half-Life: Decay?

+4 votes     reply to comment
9tdf Apr 17 2013, 4:27pm buried:


need demo of game

-16 votes     reply to comment
Headshot174 Apr 19 2013, 12:29pm replied:

i'm pretty sure there will be no demo for the game , like black mesa. but i prefer enjoy the full version of the game for first time.

+6 votes     reply to comment
EvilGoodGuy Apr 20 2013, 8:41pm replied:

basically, you can consider the multiplayer version of OBM the demo for both GD and OBM

+4 votes     reply to comment
TheUnbeholden Apr 13 2013, 9:18am says:

Would be nice if you guys could help out Hazard Team (decay: source) so that it may see the light of day.

0 votes     reply to comment
Mr.Marooned Apr 13 2013, 6:22pm replied:

Hazard Team Died December 31, or was put on ice, but they were apart of the mod at one point.

+3 votes     reply to comment
BlackHand27 Mar 24 2013, 7:50am says:

The true fans of Half-Life... Keeping it alive in anyway you can. Thanks for your works, Half-Life will never die!

+5 votes     reply to comment
Guest Mar 22 2013, 4:11pm says:

Wow what you guys, Black mesa, and opposing force source are doing are great! its awesome to see the best games ever in amazing graphics, keep up the good work!

+3 votes     reply to comment
iAmaNewb Apr 6 2013, 3:35am replied:

Operation Blue Mesa: Barney and Friends

+2 votes     reply to comment
iAmaNewb Mar 22 2013, 2:32am replied:

Black: Catch me later in 20 years to find there's no beer

+5 votes     reply to comment
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