The Challenger Deep 2

for Half-Life

2nd June 2013

Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3

This is a remake of an original Half-Life mod called The Challenger Deep.

This re-designed mod has been in development for more than 7 years and has been made by the same author.

It follows the same storyline as the original.

Basic Details
  • Title: The Challenger Deep 2
  • File Name: hl1-sp-the-challenger-deep-2.7z
  • Size : 67.10MB
  • Author: Doc Rock
  • Date Released: 02 June 2013

Download Options

Download to your HDD [67.10MB]

Installation Instructions
  • Copy the challengerdeep2 folder into your half-life folder.
  • Restart or start Steam.
  • The Challenger Deep 2 should now be listed in your Library tab.

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


Click on the thumbnails below to open a 1024 pixel wide image.
WARNING: The screenshots contain spoilers and are NOT in chronological order.

Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3
Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3
Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3
Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3
Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3 Single Player First Person Shooter Maps and Mods for Half-Life 1, 2 and Episodes 1, 2 and 3
Reader Recommendations
Avoid It!
Think Twice
Play It Later
Play It Now!

14 recommendations, average score: 4.71 (out of 5), standard deviation: 0.2 (what's that?)
Total Downloads
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Meta Review Data
Statistics based on 14 comment(s) with meta review data.

Using Gauge: Users
Manually: 14 Users

Time Taken:
Average: 4 Hours, 12 Mins
Shortest: 2 Hours by 3485343
Longest: 8 Hours, 15 Mins by john
Total Time Played: 58 Hours, 45 Mins
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  1. Firstly, thanks to Doc Rock for releasing the mod on PP first.

    It’s clear that this has been a LOT of work and the Beta Testers Collective started working with him after he felt it was finished. He made many changes and worked very hard to improve the mod. That said, the BTC feel this mod has been released too early. I can’t imagine how strong the desire is to release something that has taken this long to develop.

    I’ll write a review when I finish the mod.

  2. Play It Now!

    It’s a great mod with original concept and environment. At the same time it’s a classic style mod which is using widely standard HL resources (initial game dlls, models, sounds and big part of common textures). I can recommend this mod for anyone, who likes to play quality HL mods. Some hours of fun and interesting gameplay are guaranteed. Also, the mod works fine with Xash3D engine.

    1. Thanks for the great review and kind words. Also thanks too for your input in the mod as well as your super testing. Plus, thanks for the helpful insight here as people have played and made their comments.

  3. I always liked challenger deep even with its 2 -3 bugs. The old mod’s remind us how the game was when it first came out and was the game changer in computer gaming.

    Now off to play challenger deep 2, I wonder how long it will before I drown? hehe

  4. I played The Challenger Deep some years ago and felt it was great mod, but not enough develloped.
    I’m curious now.

  5. Play It Later

    To be honest this could’ve have used some additional testing as I ran into a few bugs during my playthrough. Optimization was also a bit rough in a few areas especially in the large open spaces.

    Either way, I very much enjoyed it despite the occasional bugs and the rather disappointing conclusion. Still, it’s definitely worth playing.

    1. You know, some bugs can be caused by Valve’s latest updates of the game engine. Most part of mods are bugged by these updates. It might be not a fault of mod’s author. All testers had to use Beta Testing mod for HL in Steam to play the mod properly, and even then some unexplained things sometimes happened for them. Also, what about optimization, it can also be a fault of engine. I’ve tested this mod as under original HL, as under Xash3D engine and yes, some areas under HL worked a bit slow, but under Xash3D they worked fine. Unfortunately, some things just can not be optimized only by a mapping, without a serious reducing of game spaces.

      You can report about those bugs you’ve found to make things more clear.

      1. Yes please report all bugs because I am considering making a ‘director’s cut” of this mod

  6. I’m really enjoying it and numerous times I have no good idea how I managed to find ways to proceed. However now I’m stuck and asking for help. This mod needs a walkthrough as much as any other.

    I’m at chdeep30a, 2 of the green noise sensitive monsters, numerous ladders and great heights. I’ve tried jumping without success to various spots just out of reach. I think the route is to go up a ladder which is out of reach, but I can’t manage to do the jump up to it. I tried sv_cheats 1 and noclip but that doesn’t work.

    Any ideas?

    1. Spoiler:
      Use a ladder near the first tentacle, then climb one level up and search for a ladder near barnacles (and climb to a zone with boxes). Then you need to perform a longjump to a ledge on the opposite wall.

      1. Thanks so much. I had tried that a number of times without success and thought that wasn’t it, but I got it to work.

        1. Dirk

          Thanks for that. I had also tried the jump and thought it impossible. Finally made it.

  7. Sorry for being a nuisance again, however I seem to be permanently stuck now. At chdeep 32e, after getting the message on the console overlooking the big room with the transporter lifted up on the crane, saying everything is ready and “the administrator’s transport is cleared for launch”. From there, I can go underwater everywhere, the doors are closed as they are in all the rooms except the air lock doors to the adjoining room. I even managed a jump on top of the vent hanging from the ceiling in that room thinking there may be something up there (no). I’ve tried blowing up stuff/doors/whatever! Sure isn’t a very intuitive design in my opinion. I really wish at this point that there was a walkthrough.

    Has anyone managed to proceed further?

    1. Spoiler:
      Try to run fast to the airlocked door after pressing the button on the administrator’s panel. Door opens for a very short time.

      1. Thanks once again! It never would have donned on me that would be the case.

  8. Play It Later

    It was lots of hours of gameplay and generally very good. I find most very good mods are both clever in their design and satisfying to play, and get high ratings. This one was clever in its design, overly clever in spots, and unsatisfying in a number of ways as a result. I gave it a Play It Later.

  9. Personal Favourite

    Really nice HL1 mod. It looked great and the gameplay was challenging but not ridiculously hard. Sometimes it took a while to figure out what to do next but the solution eventually arrived. It has really nice visuals for an HL1 mod. I played the original and this really is the next level.

    I did get stuck sometimes in small spaces when exploring and had to reload or noclip to solve the problem. Also, the endless enemies at the end part was a little annoying. But these are minor points. If you like HL1 mods this is a must play!

    1. There is also some good humour in the mod, like the medical record listing of a patient complaining of a rather delicate problem

  10. Play It Now!

    I really enjoyed the mod and found no “bugs”. I did have a bit of a problem getting the scientist to open a door with zombies behind it and the final airlock door time puzzle got me too. I no clipped and had the big fight, but never got into the escape pod. Maybe you are not supposed to.

    My only request would have been not so much big boss battles at the end and more of the original challenger deep, walking along and all of a sudden being underwater and finding an air hole or way out quickly.
    thanks for a great mod

    1. You are supposed to get into escaping pod 😉 , but there is a little puzzle, which you should solve for this. There is a computer’s message with a hint about what you should do.

      1. I just finished the mod. about that puzzle at the very end..

        the computer says that the clamps are jammed and damaging them might release them. After shooting a bunch of grenades & rockets at the clamps nothing happens. so I start walking towards the pod and then I see a cutscene of the pod leaving.,,and my HP dropping to 0

        is that what is suppose to happen?

        1. The pod should drop when the clamps are damaged enough. Then you walk into the pod, press the button, and you escape

          1. Anon_817402

            none of that happened. I just walked near the pod…I think there was a wooden box there and it just ended

            1. Hmm we’ll see if anyone else notices this but this is the first for me seeing this happen

  11. bobo

    it’s a great mod I play it 2 times very cool ..

  12. Fun mod, I didn’t have any problems with it, interesting map design and plentiful ammo.

  13. 2muchvideogames

    geez, I’m one of those guys that couldn’t get even start a new game. >_<

    1. What’s the problem – does it show up in the steam library tab? What happens when you try to start it?

      1. 2muchvideogames

        It freezes on startup. That’s alright, though, I started with chdeep_train1 instead and found out that the game always freezes if you go anywhere near the helipad. Was there a game_text spewing out a message that’s too long? I dunno, that could be one reason for the game freezing. Anyway, I played the entire mod and I have to say it has pretty stunning visuals, though a bit unbelievable for an underwater complex, but definitely impressive. The presents sidequest was a huge motivation for exploring the entire mod, but I only found like 15 presents. Compared to the first installment, there was definitely less focus on being underwater, since alot of the areas (and very large ones at that) have almost no water around. But the improved scripting and everything in this mod makes it much more superior to the first one. I got so pissed at that one part where the sci- (CENSORED)

        1. Odd that you found the freeze up problem at the beginning. Glad you liked the mod tho! Sorry that the scientist kinda ruined your day 🙁

  14. Hec
    Personal Favourite

    Well, what can I say about this mod. First, it’s been so long since I played it, in fact, this was one of those mods I played when I started in the Half life mod universe, maybe back in 2005 or 06, so it’s been so long until those times…

    First maybe I can say, this is a worthy remake of the original mod, it certainly looks that developers really wanted their creation to polish and release it as a Director’s Cut well piece of mod. and so they did a good work.

    This mod is enormous, really huge and it just feels as a classic, because it’s from those HL1 modding era which I used to call as the Total Conversion era, you know there were a bunch of mods from 99-2005 or so, which in a bundle of developers join in and modified all the HL1, and as a result we had huge mods up to 4 hours or plus of gameplay, Sweet HL, POV, Azure Sheep, Hl Visitors, are into those huge of Total Conversion classics, among them, of maybe poor quality but a good sounded project was The Challenger Deep 1.

    I guess what I like of this mod is that it’s built around one simple concept of HL and that concept is “WATER” you know water levels always will be kind of mystic from Mario Bross water levels, to here in HL1 and 2 water environments that atmosphere is a cool clean canvas to develop a cool mod.

    In this version, where all seems better polished, from textures to models, I like the hugeness of the place, the Challenger Deep Complex is like Black Mesa underwater, the plot and story is just a replica of the BM disaster, but that’s a classic feature in the Total Conversion Modding era so I agree with that.

    Combat in this mod always was entertaining and kind of strategic due to it was held in big areas, so Crossbow will be a great friend all the way…, I agree sometimes it was kind of repetitive, but the tasks in this mod only reduces to the old classic “get the heck out of there!”

    Now maybe the weakest point of this mod is obviously the ending, its totally dull, and sometimes paths to follow are just confuse, tough this “navigation” problem is improved a lot from the first version to this one.

    Overall is a cool classic, I know maybe my recommendation should be in a green play it now, but in my tremendous nostalgia array, I just will go for my heart feeling and give it a Personal Favorite recomm. Why? Because mods like this aren’t build anymore (maybe G-string for HL2 but that’s another story), is just a classic you have to try.

    1. Thanks for the very kind review. I’m glad you liked it!

      1. Hec

        No. Thanks to you Mr, you, and ur team make this great mod possible. Hope you plan some more mods to realase on the way!! 🙂

  15. Play It Later

    Sadly, I had many problems with this mod. The play was sometimes very jerky, like my pc was struggling to cope with lots of on-screen movement. The same pc plays hl2 and other shooters no problem.
    The scientist opened one door then nothing else. I presume he was supposed to operate the platform lift as well, but I had to use noclip to bring it down after figuring out where I was supposed to go. I wasted a lot of time doing that!
    The underwater section was impossible without cheating. There are oxygen stations throughout the complex, but I could get nothing from them. They made a noise when I bumped into them, so I figured I should press “e” to “use” them. I just kept drowning.
    There were places I could not reach. For example, jumping from the top of a crate to an opening on the other side of the corridor, or getting on to a loading dock to reach a duct when there is nothing to stand on. I couldn’t figure out how to get up to an opening in a huge concrete silo after killing the troops who had occupied it.
    The game has some good puzzles and is fun to play, but it was spoiled by the above. This could have been so good and obviously was for some people. I have no idea why my experience was different.

    1. Sounds to me like you didn’t have the long-jump module or weren’t familiar how to use it. Sorry you didn’t enjoy the mod.

      1. I did enjoy the game when it worked for me. I know I had the long jump module, so maybe I’m just crap at it. My frustration came from the scientist and oxygen stations that didn’t work.

  16. gage

    i can’t find the 15th present

    1. It’s in the room with the large fans in the floor that blow you up into the air vents after they are turned on. There are actually two presents in this area.

  17. redokrat

    just playing the mod now. am enjoying it, and would recommend playing it.
    could use some help as am stuck in room with suspension capsules and broken transport mechanism. thanks

    1. Ade

      Not sure where exactly in the mod you are, but you might need a scientist’s help to get out of there.

  18. Play It Now!

    I was very pleasantly surprised by this mod. I had heard the original Challenger Deep was notoriously hard, so I’d never bothered playing it. But whatever problems it might have had, the remake seems to be very well done. I particularly think it builds up suspense quite well, and the oxygen tank/underwater sections made for a very interesting game mechanic.

    Really, the biggest problem I had with it is I felt it went on too long. I feel stupid saying it, because I keep wishing there was more single-player Half-Life 1 content out there, but I felt like by the time I finished Challenger Deep 2 I was thinking: “finally!” But that might have been just me. Either way: play the mod! It’s good!

  19. Please tell me how to get out of entry-level swimming pools? Gifts collected, go in a circle and all the doors are closed ((

  20. Play It Now!

    Classic Half-Life gameplay. Most of the puzzles are ripped straight from Half-Life with some new ones. You better master crouch jumping before you consider starting this. Its a mod that is mainly aimed at Half-Life veterans. The levels are huge and the mod maker is really good at catching the player off guard. I was playing on hard and I admittedly found myself save scumming more then I usually do. The mod’s length is considerable. Its very good at capturing the feeling of the original Half-Life. It is more Half-Life gameplay, but it is very good Half-Life gameplay. If you want more Half-Life, but grow tired of the original campaign after playing it for the 100th time this mod is for you.

  21. A Strange Stranger

    I only got one file. It’s named hl1-sp-the-challenger-deep-2.7z I need a folder to put in, and I am unknown to 7z files. Any help?

    1. Forgive me for sounding churlish but there is a link in the post that says “If you require more help, please visit the Technical Help page”.

  22. good

  23. Play It Now!

    This mod has the most unique atmosphere I have ever seen. Underwater environment is criminally underused in Half-Life mods.

    Challenger Deep 2 starts slow, you walk around the beautifully created underwater research lab, learn the basics of diving and using oxygen tanks ( which this mod uses a lot ) and start collecting the optional 20 presents along the way. The presents are scattered around the facility from start to finish, you don’t get a reward for collecting all of them, they are like the creator explains “a fun side quest ” think them as Half Life 2’s Lambdas.

    After the classic catastrophe, you stumble upon your first and most dangerous enemy: Water.
    scarcity of oxygen tanks and ichthyosaurs combined with the huge levels makes the water feel like a real enemy. Of course you also have your standart grunts, zombies, gargs, vortigaunts etc.

    Another neat feature is terminals. You can read the computer terminals to better understand your situation, see other scientists logs etc.
    It’s fun and extends the mods playing time, speaking of time, this mod is long. Took me nearly 3 hours to finish.

    There is a part of this mod which a scientist accompanies you on your journey, I will not give any spoilers but I will say this: keep an eye out for him, you’ll never know…

    Decent mod.

  24. Play It Now!

    Very good mod. I was suprised by the fact that it was so long. Clearly alot of time has been sunk in this mod, and the result is a good Half-Life experience with some really fun combat.
    Though I was at times stuck not knowing where to go, I had to search up a playthrough at one point because I had been looking for the next path for quite some time. The rest of the mod makes up for this though.

  25. Play It Now!

    After years of develop of the old one you really improved, interesting fact that its set on an underwater facility instead of regular old Black Mesa.
    A very fresh start.

    REVIEW The most confusing part of the game is the water/underwater sections and some of its puzzles felt like a maze because of constant backtrack (I’m bad at puzzles :P) it took me 3 hours and 50 minutes to complete but it was worth the time I spent.

    though the Puzzles are the only thing i’m complaining about , so its very required you have a good eye and observe the area well enough. (especially on the rocket part)

  26. Play It Later

    The Challenger Deep 2 takes the Resonance Cascade miles deep under the ocean.

    While the story is almost the same with Half-Life, I do appreciate the plot twist with the scientist and the ending. Also, due to this mod being made long after Half-Life was released, the areas are noticeably more decorated and livelier than the original game. Some areas are very huge and expansive too. You will also encounter many Ichthyosaurs here, referring to the dialogue of a scientist in Half-Life, but you will try to avoid them most of the time. Also, I’m not sure why would they set up rockets to launch under the ocean.

    The gameplay is your classic Half-Life gameplay. There’s also this rebreather thing where you can temporarily stop yourself from drowning. Although I wish that they weren’t single-use items.

    This mod is not without flaws. The part that involves you setting up the rocket feels very irrelevant and doesn’t contribute anything to the story. As stated, some areas are very expansive, but a few of them take it a bit too far and it left me confusing. The finale is also too frantic for the player to both fight and release the submarine at the same time. The soundtrack of this mod is obnoxiously loud, it always drown out the game’s noises whenever it plays.

    Throughout my playthrough, I also sort of noticed that during both encounters with the Gargantuars, the mod probably couldn’t decide to make it either a chase sequence or a mini-boss sequence. There are explosives scattered around the area, but the level design also screams of chase scenes.

  27. Personal Favourite

    This is a great mod! It has a really unique idea, i never really thought about a Half-Life mod that takes place underwater, i’m surprised it works really well. It has great level design, gameplay, and it’s not too difficult to the point that it becomes unfair.

    It isn’t perfect, though. Some areas were hard to traverse and didn’t have clear hints as to where to go. I had a weird bug where the airlock door in the room with the vertical moving platform didn’t open at all, maybe i missed something but when i watched a walkthrough online that door was supposed to open. I had to noclip to get in but luckily the eye scanner on the other side could open the door and let the scientist through.

    Overall i think this is a great mod, and i highly recommend it.

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