Military Duty

for Half-Life

You are Alexander Shepard; Corporal and a soldier of the Hazardous Environment Combat Unit.

You don’t know exactly what’s going on. But orders came in to pack up everything and head out for a highly classified mission.

The destination is Black Mesa Research Facility.

Nobody knows for sure what has happened down there but you will find out soon enough.

Basic Details
  • Title: Military Duty
  • Filename: hl1-sp-military-duty-v1.0.1.7z
  • Size : 111MB
  • Author: 23-down
  • Date Released: 28 June 2015
  • Date Updated: 28 August 2016
Author’s Notes
  • This is my first release.
  • This mod has linear map progression. I was never a fan of backtracking my way in Half-Life. I rather show new maps instead of the same ones over and over again.
  • Recommended difficulty is hard — easy is simply put too easy as you will rush through the maps without probably ever dying just once.
  • There are 3 minor glitches my mod suffers from. See below for more details.
  • Try not to use noclip at all as you may break certain scripts within the maps unless of course you might get stuck in some walls or so. But I think I made the way always rather clear in most maps so path finding issues shouldn’t occur.
  • Approximate playtime depending on your skill and if you linger around or not between one and two hours.
Known Bugs and Glitches

This mod has been designed to work with the Steam version of Half-Life NOT the WON version.
In various maps you will travel per train. Now I did try my best and in 90% of the cases it’s also working charming: But please do not jump around inside the train when a map change is about to happen. Also when the map is about to change stay on the front section of the train and not in the aft section. At least in 1 map I noticed that when you’re in the aft section of the train that the map transition wont always work. I don’t know why that is. Because the way I designed it the mapchange should trigger no matter where you’re standing. Also try to stay in the middle away from the walls to your left & right. After like 60 run throughs I experienced it one time that I got stuck inside the train walls after the map change. Better safe than sorry.

In one of the maps is an Osprey. If you’re very good you can kill it rather fast and easily. I’ve tried increasing it’s hitpoints. Unfortunately that’s hardcoded and can’t get changed without a custom code. So best not kill it immediately – in order not to ruin some tense moments. Though no worries the game will progress with or without it on the field.

There are some beams in one specific map. I noticed that after loading a game these beams are no longer working for some reason. But so far only then. I don’t know why that’s happening but it has to be a glitch by Half-Life. One that I can not fix. The issue simply makes no sense.

Download Options

Download to your HDD [111MB]
You can still use it with MapTap once you have downloaded it.

Manual Installation Instructions
  • Copy the Military_Duty_v1 folder into your …\Steam\SteamApps\common\Half-Life folder.
  • Restart or start Steam.
  • Military Duty should now be listed in your Library tab.

If you require more help, please visit the Technical Help page.



WARNING: The screenshots contain spoilers.

1024 x 576

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Reader Recommendations
Avoid It!
Think Twice
Play It Later
Play It Now!

8 recommendations, average score: 4.75 (out of 5), standard deviation: 0.44 (what's that?)
Total Downloads
  • 3,568
  • 2
  • 33
    Last 7 days
  • 156
    Last 30 days
  • 2,290
    365 days
Meta Review Data
Statistics based on 8 comment(s) with meta review data.

Using Gauge: 0 Users
Manually: 8 Users

Time Taken:
Average: 5 Hours, 27 Mins
Shortest: 1 Hours, 5 Mins by olof.
Longest: 20 Hours, 30 Mins by Thanoshld
Total Time Played: 43 Hours, 38 Mins
Jump to a review
Personal FavouritePlay It Now!Personal FavouritePlay It Now!Play It Now!Maybe?Play It Now!Play It Now!

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  1. Firstly, I’d like to thank 23-Down for choosing to release this exclusively through RTSL. Things like that really help the site.

    Secondly, I am still unable to type or use a mouse for more than a few minutes. So, even though I am listed as a beta tester, I only tested very little.

    Also, it means that I haven’t finished the mod and it may be another week before I can play games.

    I hope you enjoy this, as we don’t get enough GoldSource mods any more.

  2. Thanks for the quick upload Phillip and I do hope you will feel better soon.. 🙂

    As for you people I’m looking forward to many great reviews. I’m aware there are few minor glitches remaining in the mod. I will address these with a future patch so no worries. Would be lovely if you’d dropped few lines telling me what you thought of the mod… 🙂 Till then have fun.

  3. It keeps crashing on me in map 6.Tthe area with the heavy double doors and the g-man. Anybody know what that is? I play a non-steam version under windows 7.

  4. During my mapping I noticed that the old WON version and steam version of the Half-Life games aren’t always compatible. In won for example textures that were supposed to be transparent were blue. Also the path finding etc. is somewhat inferior compared to that of the steam version. I suggest you play it on steam period.

    1. I understand what you’re talking about, but after I patched the WON version with the unofficial patch, all of those problems were solved. Also, about that crash, you just have to reload the save and it will work.

      1. Well, I tried the patch, it works at first, but then it craps up on me again later. After a while even the saved games won’t work anymore.
        So I guess it’s steam or nothing, haven’t decided yet…

  5. Personal Favourite

    Look, I may be exaggerating a bit here, but this for me is simply one the finest Half-Life 1 mods to date.

    I loved all of it. I loved the combat, the environment, the new textures and models and the fact that it combined HL1 weapons with OF weapons. I also liked the fact that it was very long, but it also managed to not feel tiring or boring.

    Do I have complaints? Well, the ones I have are minor really. The crashes only occured at 2 maps for me in the WON version (map 6 and 14). Also, some enemies were not that well placed, but it was really rare.

    Overall, for a first try, this is unbelievably surprising and you should definitely play it. It’s really nice to see that people still mod HL1 to this day (with good results).

  6. Play It Now!

    This little mod is pretty good. I liked seeing the OpFor characters and weapons again and the story is pretty interesting. The intro takes a few minutes but that is just like Opposing Force did. You don’t really get to use your soldiers that much but they are helpful in a few spots. The Xen part was short with relatively easy combat but it has a pretty good battle at the end. I thought the mod’s overall ending should have happened after you boarded the train but still it was fine. It’s a fun little mod to play and if you liked Opposing Force I think you will like this too. I do recommend you read the author’s notes about a few bugs to work around, but these are minor issues.

  7. Looks good,, but on the second map I get a
    fatal error–
    “Mod_NumForName:Models\LGIBS.ndl not”

  8. @Pedro_The_Swift: Hm that’s odd but during development I too had it twice that the game asked for models that per google search didn’t even exist. I can only imagine that some custom models I use required some others once these got killed into pieces. You can fix it easily though. Just go to your models folder look for any other gibs model & make a copy of it. Rename that copy to LGIBS.mdl = fixed and done.

  9. Personal Favourite

    Well, what can I say. It was a long time after I played a decent GldSource mod set in the Half Life universe. And this one is more than decent. This is epic. From the very start, till it’s climatic ending.

    The story simple: You are a HECU soldier, trying to cover up the whole Black Mesa incident and ending up fighting for your own survival. But, in this mod you can actually see the huge mobilization of the HECU military division (trucks, jeeps, tanks and equipment laying around) and their struggle to contain the alien invasion, things you rarely see in Half Life mods.

    The quality of the mapping is superb, the general layout and architecture of the maps is interesting and comprehensible (as to where to go) and the scripted sequences really bring Military Duty’s world to life.
    The enemy placement and spawns are well placed. I never encountered an absurd amount of enemies, neither have I come across endless, empty corridors with no signs of life.

    It had many memorable moments along the way: *spoiler* The train ride, the Gargantua fight and of course the ferocious end fight for your escape, to name a few *spoiler*.

    And one of the mod’s more important asset is it’s length. I have played many GldSource mods that are under 30 minutes of gameplay. I played Military Duty for almost two and a half hours. And that’s one of the things I liked the most. It was not a demo. It was a full game.

    To sum it up, this mod is a refreshing addition to the GldSource modding scene. A must-play for every fan, not only of Opposing Force, but of Half Life in general.

  10. Play It Now!

    What an enjoyable experience!

    Overall this is an incredibly impressive mod. Locations are unique and interesting, whilst still feeling extremely routed within the Half-Life universe. Vanilla assets are used alongside custom content in such a well-balanced way that you instantly accept the world you’ve been dropped into.
    The facility feels like it’s alive and NPC scripting and detailing is at an exceptional level. There’s always loads to look at, and that really helps keep the mod fresh over its surprising and impressive length.

    So please keep in mind that I am a huge fan of this mod, but I’m now going to focus on a few reasons why I’m not quite putting it in the ‘personal favourite’ category.

    Firstly, there are repeated occasions where level transitions are rather jarring. This happens most notably in the intro, but also several times throughout the mod as a whole. Huge changes occur between maps that could be better hidden with a fade or with a more enclosed level change. It’s a minor gripe, but it occasionally left me a little disorientated and unclear on what had happened around me.

    Second, I was slightly disappointed at the lack of actual puzzles. The closest we really get to a puzzle is finding a button, pressing it and then only finding out what it unlocked afterwards. More signposting for where you need to go would reduce the feeling of “I wonder what that button did”. Also, more carefully thought out puzzles in general would be welcome relief from gameplay which is unfortunately just combat from start to finish – to the extent that around half way through I was finding it quite grating (though it got a lot fresher again towards the end).

    Though there are exceptions, I found the lighting to be somewhat lacklustre throughout. There are some beautiful examples of good lighting, but for the majority of the mod, the lights are simply there to illuminate rooms, rather than to add atmosphere and character to them. The biggest exception to this is in the loading bay where the tram ride finishes – it’s absolutely stunning in both design and lighting. More of this!!

    Aside from what I’ve already said about lacking puzzles; gameplay-wise the mod is very strong, albeit with a few irritations. I constantly only just had enough ammo and health to proceed, and that suggests that it’s fantastically balanced. It was a genuine challenge, but never utterly ruthless. Fantastic. The irritations were firstly an overuse of unfair monster spawns right behind you that required quick loading if low on health and secondly a major overuse of barnacles. Barnacles aren’t a challenge, and they’re ok to have occasionally, but in the quantity they’ve been used here they are really annoying.

    Finally, though it was clearer towards the end, I felt like a more overarching purpose would have made the mod more enjoyable. You’re told at the start that the objective is to kill witnesses to the Black Mesa disaster, yet doing so actually fails the game at least once (killing a scientist needed for a retinal scanner). This leaves the player somewhat lost for purpose, and lowers their guard when Barneys are first encountered.

    I know this seems like a lot of negative points, so again I’d like to stress that I really love this mod! It’s hugely impressive, hugely ambitious and extremely well executed. I’m just being very critical because it’s so close to being perfect! 🙂

    Congratulations on releasing this, you’ve done brilliantly.

  11. This little mod is very good.i enjoy it, !!!! thanks for this.

  12. Heinz

    Hey Hey,

    you are ill…that was one of the reasons for asking you to help in any way, but you said you want to administrate your page alone. Okay for now it doesn’t work, huh?
    I did not ask for administration, I am not a coder or anything like that, but I am surrounded with computers since C=64 times in early 80s and very talented in learning new things and getting better in already learned things.
    But okay, I wouldn’t trust everybody over the internet, too.
    Hope you get well soon, that is the number 1 important thing, not posting anything.
    Take your time and sorry if my english sucks, it is not my mother language!

    Greets from Germany

    1. Hello Heinz,

      You contacted me from a specific post about looking for a coder. Okay, you can’t code, no problem. I replied and asked you what you could do but received no reply. Administration means posting maps and mods etc. However, I run the site because I enjoy doing it. Getting somebody to post the maps and mods isn’t what I am looking for.

      If this were my job or I made money from the site then perhaps I would look for different help.

      Anyway, sorry I haven’t updated the site recently.

  13. Wow we’re reaching the 500 download count. I would’ve never expected this that there are still that many people playing Half-Life1 it’s wonderful and my gratitude to each one of you. Feel free to write a review with your opinion and raking it it.. 446people downloaded yet only 4 wrote a review. Don’t be shy I can take it.. 😛

    Greetings 23-Down

  14. Hello all

    I like this mod, I liked to play opposing forces, it was a long time ! just for me this mod need a bit of work about the level design and to change few textures and align them.

    But good work I liked especially pnj fights 🙂

  15. Hec
    Play It Now!

    This is outstanding by its own. I mean, as far as I understand this is a nowadays Goldsrc HL1 mod release. And that’s just pretty nice, as almost not mapper at all still have projects or maybe very little projects developing a “from scratch” HL1 mod these days.

    Now into the mod itself. I think all the maps felt pretty fresh, and with a nice realistic BM design all the way. It was indeed pretty nice to see that BM real scenario again.

    The OF weapons and enemies were delightful but the ammo supply was scarce at least for the M50 machinegun, so that was a turn down for me.

    Also the combat was fair and fun to play all the way, so possibly my only general complaint about this mod, is about the end. For me it was kind of unexpected and the final battle felt just very plain. I think maybe to battle a Gargantua in there could’ve been cooler that those combat against the angry Barnies.

    In conclusion, this is a quite fun enjoyable, HL1 nostalgic mod, you must try if you love HL1 classic good old combat mods.

  16. Help! I’ve not gone far and am stuck already. I jump over the pile of sandbags to find corridors at left, right and straight ahead but no way out.

    1. Please ignore above. I see where to go next.

  17. Maybe?

    We start in the helicopter, and see the landscape through the door, like in Opposing Force, except it doesn’t look as enjoyable despite the scale of the structures. Something is missing. What could it be? Maybe it’s the monotonousness of the place – only walls with cliff textures, and no smaller mountains? Maybe it’s because sky used is not “cliff” one, and “cliff” would look better? Then weird structures appear: Towers of cargo containers that are higher than mountains and the crane textured with yellow and black stripes. One of those containers has misaligned texture.

    Then there’s tunnel where gradient to darkness is not smooth but with rough quick transitions between colors as if the author just connected few brushes together, each having darker version of the texture. Then if you turn on your night vision, you’ll see that the tunnel quickly ends with a wall textured with “black”. To the right from it, there’s a sign with jpg compression artifacts…

    We look around and see an uninspired rectangular courtyard, there’s an uninspired corridor in front of us, its walls are shapeless and are textured with “rock” textures.

    Few moments later we’re in another couple of rectangular courtyards. One static mesh disappears from time to time, one rock wall has a missing triangle, the door looks like solid rusted wall…

    Mostly the whole mod is straight corridors and rectangular rooms with too little architecture to look at. So, the design is mediocre. Sometimes we see textures taken from Half-Life 2 which look out of place here. Despite the simple design, framerate drops at times.

    On a positive side of level design, some curved surfaces look more smooth than Half-Life engine is capable of: textures are perfectly aligned and imitation of smooth shading was used during lightmap compilation. Rough edges only appear if you turn on night vision and come closer.

    There is nice atmospheric lighting in the canals but it can’t hide boring flat walls because we have night vision.

    After the canals we get into cramped corridors with flat walls. The place looks like the author deliberately made it cramped to spend less time making it look good: flat walls don’t look so bad in such small space.

    Explosive barrels don’t explode, making us waste ammo in vain. A button with the texture of medkit is a neat way to show a malfunctioning one: you try to use it, but only turn the light on and off. Never seen anything like this before.

    Timing is off in the script with falling scientist: he falls and disappears, and then after some delay, gibs appear.

    There are some interesting moments: Barneys as enemies (unusual, interesting and difficult combat situation), alien running through the vent with loud sound, cool train ride (which, unfortunately, might be spoiled by chance of getting stuck in the train) and following battle with black ops, Garg that throws cars around, prolonged fight you see from the window: HECU vs Black Ops, then scientist and two Barneys appear, then Alien Grunt gets dropped in the area. And overall variety of battle situations and given weaponry is pretty good.

    Xen levels are balanced really well: health is scarce but just enough to complete them.

    Overall, it’s not a bad mod, but the author’s tendency to do simple rectangular rooms and corridors with flat walls really spoils the impression.

    I’d like to finish by telling this to the author: please don’t get discouraged by this review. You have potential and when you learn how to make beautiful architecture the quality of our work will greatly improve.

  18. Thanks EmoLevelDesigner.

    While I still think that your rating with maybe is bit harsh considering how many other maps and mods are out there that consists only of purely blocky mapping and bad texturing or lighting I admit you’re right in several of the cases. I will see that I improve upon that and you’ve got a good eye on things as well as the med station. I simply didn’t know how other mappers did it that it plays the empty sound and the proper animation as there weren’t any health_station_empty entities to choose from.

    As for the Hl2 textures there are 0 in my mod to my knowledge the only texture referring to hl2 was that with Breen on it. The remaining textures were either self made – default hl1 series tex or from other hl1 mods on “free to use basis” if these wads. contained hl2 textures I can’t tell as I’ve never mapped for hl2 myself.

    Anyway I thank you for your review and regarding room design you’re also right. My biggest problems are usually ceilings or making a room look realistic by looks & architectonic standards. But I think you could have also written a bit more about the actual gameplay in this mod. Your review focus almost solely on graphical aspects and please consider this is a game of 1998 not Unreal Tournament 4 or anything else for that matter.

    So you too please don’t feel discouraged by my analysis of your review and focus on all aspects of a game or mod not mainly just on graphics and architecture (though they too are ofc very important!) Looking forward for your future reviews as you write em good and don’t hold back on anything. So thanks for that. I will see to improve upon your suggestions. 🙂

    Ps: I hope you still enjoyed the mod. 🙂 ‘Cause enjoyment was my priority.

    1. Thank you for replying to the review.

      To map with blocky mapping, bad texturing and lighting I’d give a “Think Twice” if it had fun gameplay, and “Avoid It!” otherwise.

      Since you ask for something more about the gameplay, I can recall a nice situation where Alien Grunts ambush you and you need to realise that Spore Launcher will work great against them. And there’s also a place where you can use Barnacle to get across a broken bridge or something – attempt to collect the spores led me to falling down too easily and I’d appreciate if those spores were more accessible.

      If I expected every Half-Life mod to have graphics like in Unreal Tournament 4 they’d all get “Avoid It!” rating from me. Even a 1998 game can have levels with good-looking architecture. Have a look at “Operation Myrrh” and “Infiltracja” mods – they’re like a big list of examples that shows many original and inspiring rooms and corridors. And “Typical Disaster: the Lost Levels”, where each level is more interesting than just flat walls, and also maintains its own style throughout.

      You can also see examples of interesting architecture and landscapes made despite limitations of the engine together with requirement to run fast enough on less powerful computers people had at the time in original Half-Life, Opposing Force and Blue Shift.

  19. 23 Down, I am playing (on Hard) and I cannot see any gun sites..think that is what they are called…those little yellow circles that help you place your aim. I am wasting ammo because my aim is sometimes off. Can this be fixed by some command in the console? I am really eager to play this game, loving it so far.

    1. The reticles finally appeared on the revolvers and the shotgun, but not on the machine gun. Loving it so far, but I have a game glitch. Sometimes when I save, the screen goes black and I have to use Ctrl Alt Del to shut the game down. If I reload that save, the screen is black and doesn’t run, and I have to again use Ctrl Alt Del to shut the game down, and then to go back to the previous game save to restart the game. Not sure exactly the situation when this happens but it could be when a new area is loading, has happened twice when loading a new area. Currently I am experiencing this at Mil_duty6, has happened 3 times in a row where I have to go back to the beginning of the level, as all game saves take me to a black screen, that says “Loading,” and never starts the game. Thanks!

  20. Problem solved, and Spoiler alert!
    I went back to restart level Mil_duty6 saved it to my “stuck” point and it reloaded fine, so for now, I’m good. However, I am stuck here. Do I need to save all the scientists on this level for a security lock somewhere? I activated the bridge, killed the thingy behind the sandbag barrier. Managed to use boxes to climb over, which took awhile because they kept floating to the ceiling…had to work fast. Then I could find nothing to do but couldn’t get back over the sandbag barrier, so started over at the last save. I am stuck here…anyone want to give me a clue?

    1. I figured it out. No need for the clue…was really tough to find…love this mod!

  21. I think I found another glitch. On Map 7 there is a room with a small train..single car. When I get in, the door closes but then my avatar gets stuck and cannot move. Is there supposed a train ride here? I have re-entered the train about 6 times, even tried the elevator remedy of jumping up and down to avoid getting stuck but it doesn’t help.

    1. Spoiler –
      I finally used noclip, to get unstuck while riding the train at the beginning of level 11, even though you warned against it. It was the only way I could move. Did others have this problem?

  22. Hi ya that train bug and getting stuck seems to be happen for numerous people while others don’t get stuck once… It’s very frustrating to say the least.. Noclip was the right course of action in that case.

    As for your missing crosshairs that must be on your part. Try these console commands:

    cl_drawhud 1
    crosshair 1
    hud_quickinfo 1

    not sure if they work in hl1 as these are from hl2 but at least the crosshair command should work.

    As for your black screen bug. Not sure what caused it I suspect you’re playing this in the non steam version. Map6 and 11 or 15 tend to crash in that case. Loading a savegame prior to the crash or restarting those maps per console solves it though.

  23. Play It Now!

    I had a great time playing this mod. I played in Steam. I played on hard, so that may be what gave me some problems, including in 3 places where I ended up using noclip to execute required moves. I did have some crashes in the beginning, which are discussed in my comments above. Other than those problems I reported in my comments, it ran smoothly. Playing time is satisfyingly long, and the sound effects and background dialog are clever, and at times amusing. I actually played for 12 hours, but the Time Taken blank only allows 1 digit. Great accomplishment for a first mod! Thanks 23-down for responding to my questions in the comments. The crosshairs did appear toward the end, though very faintly.

  24. Play It Now!

    !My First review on this site!

    Quite nice mod. Starting with classic ”Half Life: Opposing Force” intro, what is very nice becouse I like that kind of opening sequences.

    This mod is very classic, but have many good scripted moments. When I played this some times ago, I Felt really nice climate of big H.E.C.U. invasion on Black Mesa.

    Design sometimes is very good, but sometimes is very bad. There are some bugs too, but when I played this, I did not see them often.

    Very nice medium length mod, I enjoy it!

    Sry for english in this review.

  25. Half-Rats

    A fun play! Really enjoyed all the new enemies. Also…the beginning – Was that the discourse from Operation Flashpoint? (ARMA I) Yes. Yes it was.

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