Black Mesa Sideline (Half-Life singleplayer mission)


- version 2, multilingual (en/ger), steam compatible
- released on Jul 5, 2007 - originally in Jun, 2002
- contains 17 maps (plus 3 in-/outromaps, 5 trainmaps)
- used Worldcraft Ed. 3.3, HL Model-Viewer, Sprite Viewer, Sprite Wiz, PAK-Scape, Wally, Gensurf
- based on Half-Life 1009


The Story of Underground continues the original story of Half-Life. As Gordon Freeman, you are sent on a mission to the distant north bunkers of Black Mesa. While you are looking for the Xen aliens, you have to cross small ventilation shafts, derelict maintenance areas and dark laboratories. You may be "underground" but the only way out is to go deeper...


Half-Life Underground was my first and only official continuation of Half-Life. Anything I created after it was not finished or unrelated and too small to be a fanmod. Underground was original released in the German gamemagazine PC-Action in 2002, nowhere else. As I worked on Underground I already had one year's experience in working with the Worldcraft editor. I’ve never worked so long and hard for one single project since.

Greetings ToTac

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Half-Life: Underground v2 (en/ger, steam)

Half-Life: Underground v2 (en/ger, steam)

Jul 3, 2007 Full Version 9 comments

Underground is a Half-Life singleplayer mission. It contains 17 maps and is fully compatible with HL-Steam and HL-Won. This download includes the gametitles...

Post comment Comments  (0 - 10 of 14)
Rallymen007 Aug 31 2010, 9:17am says:

Just finished this mod, it was really good. The only bug I had is a crash at the ending (when the ToTac logo appears) but that's the only problem. It lasted a few hours (did not count them, and they are split between yesterday and today), wasn't boring. The only thing that disappointed me is the lack of the HEV at the start of the game, it's not a big deal, and it gives a new feeling when fighting without indications about your health or your ammo.

Also, at the end, it's not evident to know you need to jump in the back of the truck, maybe trigger the ending after the death of soldier, or the entering of the tunnel.

I would recommend this mod if you enjoy playing Half-Life and want a few hours of fun.

+1 vote     reply to comment
Fuzylogic Nov 30 2009, 2:46am says:

i have a problem when i start i always get stuck at the start the train does not let me leave it i get stuck i try using noclip but no luck
and also i cant move thats why

+1 vote     reply to comment
Rickmanhacks Aug 25 2009, 3:41pm says:

I think it is not working because I do not have the suit on. Do you get the suit later in the game or do you start with it? Or do I have to reinstall it?

+1 vote     reply to comment
mokies Aug 17 2008, 6:55am says:

Just finished playing it... I love the mod but it gives me a bad ending... it crashes... when the Totac Logo's shown... :)/:(

+1 vote     reply to comment
Alien_Firefox Aug 11 2008, 2:33pm says:

needs to be a black ops

+1 vote     reply to comment
Kilroy1337 Jun 7 2008, 6:19am says:

cant get it to work!!!!
restart steam dosent help

+1 vote     reply to comment
dethtoll Mar 2 2008, 4:05am says:

I'm going to give this a shot, though I must say that I really wish people would stop putting Gordon Freeman as the hero in mods.

+1 vote     reply to comment
Guest Dec 6 2012, 10:22am replied:

This comment is currently awaiting admin approval, join now to view.

Warrior520 Jan 6 2014, 3:29am replied:

but it feels boring playing a same person in many mods you know??

+1 vote     reply to comment
Alfrodos Feb 20 2008, 9:41am says:

i can't play on it, it isn't appeare at steamgamelist -_-...

+1 vote     reply to comment
dethtoll Mar 2 2008, 4:03am replied:

Try restarting Steam, dude. Either that or you installed it wrong.

+1 vote     reply to comment
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Released Jul 5, 2007
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First Person Shooter
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