Black Mesa

Black Mesa

1,224 ratings
On a Rail Uncut
File Size
539.423 MB
Jan 24, 2016 @ 5:34pm
May 1, 2018 @ 4:08am
12 Change Notes ( view )

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On a Rail Uncut

Text FAMGUY1's (real name: Chon Kemp, now a Black Mesa Developer) project to finish "uncutting" Black Mesa. This mod extends Black Mesa's On a Rail back to the length of the chapter in HL1, by adding 4 new maps in between the existing Black Mesa ones.

IMPORTANT: You must start a new game to use this (though you can start from any chapter you like) - do not use existing saves!



  • The Black Mesa dev team for creating such an astonishing game with fantastic maps! The astounding quality of their maps really inspired me to become a better mapper.
  • Valve for creating the amazing Half-Life universe in the first place, and their groundbreaking series.
  • Dejan for writing the pieces "The Year of Death," and "Dark Skies," used on A2 and B2 respectively - written for Community Project 12. Brilliant bits of work. Hopefully my maps do your work justice.
  • The Empire (Andrew Bastian) for writing the piece "Lights Out," for me; a beautiful chill piece I use during the ambush on B1. This piece is still a work in progress, feedback is welcomed - but be nice!
  • Impetuous for skinning the construction and office workers (skinned from the BM Dev team's original security guard and inspired by Mr Someguy's attempt) found throughout OaR Uncut. Great work!
  • dead-brushes and KeepWaiting from DeviantArt deserve credit for the blood textures used on the office workers.
  • Mr Someguy for providing me with a working hexed model.
  • Maestro Fenix for creating part of the skins for the construction worker model, and also helping me solve several annoying bugs with my custom models. Thanks a lot!
  • The community at large for providing me with tonnes of feedback and giving me tips and tricks on how to make things work and how to design areas. This project wouldn't be where it is today without you guys.
  • Everyone involved in the feedback for ST Uncut. Had ST Uncut not been successful, which undoubtedly would not have happened without the community's support, I would definitely not have been inspired enough to move onto this project.
Popular Discussions View All (18)
Jul 1, 2018 @ 12:05pm
Will this be added to the official update, just like the "Surface Tension" maps were?
As Jr Won Wiki Income
May 12, 2018 @ 2:31am
December update compatibility
Jun 15 @ 10:00pm
Bug Report
Mikel S
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arbitrarylogic 3 hours ago 
I miss the loops and switches of Half Life OaR, and I was super disappointed they didn't show up in BM OaR, and the disappointed again that they aren't here either. I know there are gameplay reasons to cut the loops and switches (i.e., they confuse some players), but without the illusion that I control the tram, the map feels aggressively linear. :(

Still, thanks for the hard work on this version, BM team. It filled in a couple moments I remember fondly that were missing in the release version.
| \_/ () Oct 18 @ 11:22am 
Yup. I turned off the bublic beta and everything works fine. So after Xen comes out of beta, one might have to check if this mod is still working correctly.

I played it and I'm impressed with the work done. I did think it's a bit too long and same-y in comparison to the other chapters, especially when playing on hard, so I see why it's been cut out. However, I expected that to be the case before playing, so it was fine.

The ambush in B1 I liked very much. Also the open area on the surface gave the mappack some more variety which I liked but the downside is that that wide space would benefit from having the crossbow for long distance combat, but you don't get the crossbow untill the next chapter :/
| \_/ () Oct 17 @ 9:13am 
Please help!

Every time I start On A Rail (or the earlier chapter Power Up and then get to OAR) I have no music and some sounds seem to be missing: some footsteps sounds, sound of health charging, etc.

I unsubscribed from the OARUC mod and the game appears to run fine, with music, with sounds.
I subscribed to it again and - same bug. So it seems there's something wrong with the mod.

I really want to play this but I don't want to play a broken version. Any suggestions?

EDIT: Is there any chance I'm getting this bug because I'm having the public Xen beta on?
Cilo Sep 26 @ 10:36am 
The Marine AI in the train yard and in the warehouse before the train yard are fucking retarded. Something needs to be done about it. Other than that... pretty solid addition to BMS.
Kurama (Sean) Sep 17 @ 11:48pm 
I just want to say great job for making one of the more boring levels of "Half Life" really good, I know it probably won't happen but I hope it gets added to the main game.
SNIper of DARKness Sep 10 @ 12:46pm 
Highly Recommend it, couldn't tell which parts were added by this mod, it all linked perfectly.
@Alexstorm8840, No, it's for future
Alexstorm8840 Aug 31 @ 1:28pm 
Hello, has Xen levels be officially released? My game shows till chapter 14, starting from chapter 15 it shows just a gray image of the level.
Vigilλnte :-) Aug 12 @ 4:53pm 
It is cool, but, for some reasone, the game soundtrack doesn't work correctly, idk.