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 Post news Report abuse Latest News: 2014 Kickoff Update

27 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  (10 - 20 of 1,455)
callumbartlett77 May 16 2015, 7:16pm says:

There's a lot of comments going on at the OBM page so I'm asking here. In Opposing Force you get a lot of weapons early on. For example, you get the wrench at the beginning and then the knife less than 5 minutes afterwards. Will you be changing the spacing between getting weapons?

+1 vote     reply to comment
MR.sugar Creator
MR.sugar May 18 2015, 4:47pm replied:

Same answer here :). Playtesting will show, but will be slightly alterted probably

+2 votes   reply to comment
USMarineCarl May 7 2015, 7:42am says:

Black Mesa Source
Guard Duty Source
Operation Black Mesa Source
Cool XD!

+1 vote     reply to comment
Jonex_ May 11 2015, 10:04am replied:

None of those games legally have "Source" after them. They are not made by or affiliated with Valve. Which is why the recently released Black Mesa is called Black Mesa and not Black Mesa Source.

+1 vote     reply to comment
4Simp@ElectroShock May 16 2015, 11:16am replied:

So how about the mod titled "Jaykin Bacon: Source"? Why Valve didn't ask the mod's creator to rename it to simply "Jaykin Bacon"?

-1 votes     reply to comment
Crypt May 16 2015, 11:55am replied:

Black Mesa was *asked* by Valve to remove "Source" from the name so that the less knowledgeable wouldn't confuse it for being an official Valve installment.

No one's gonna think Jaykin Bacon is by Valve.

+2 votes     reply to comment
Ikill4fun32 Jul 8 2015, 4:39pm replied:

People still did confuse it though... I've never seen so many people yelling "WHY REMAKE GAMES AND NOT MAKE NEW ONES" and i just sit back and think, wow, what idiots

+1 vote     reply to comment
TheMuffinMan2360 May 4 2015, 4:24pm says:

Which mod do you put more work/time into as a group? Will this affect the development speed of Guard Duty?

+1 vote     reply to comment
MR.sugar Creator
MR.sugar May 6 2015, 2:25pm replied:

A lot of assets is shared, so it's more about the level designers. We try to dedicate our work to both projects equally.

+2 votes   reply to comment
Mr_Walrusman Apr 29 2015, 6:16pm says:

When will we be getting a update?

+1 vote     reply to comment
MR.sugar Creator
MR.sugar May 3 2015, 5:12pm replied:

There is currently no ETA for an update. We just work behind the curtain. for now.

+1 vote   reply to comment
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