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BMS Classic - Office Complex (v2.00)

For visibility. Office Complex was last updated in April 2021, and it's undergone some significant work since then. This also gives users the choice to stick to the older versions if they prefer to, since BMSC v2.0 features some more drastic changes from the base Black Mesa maps.


BMS Classic started out as a simple mod aiming to undo some of the changes brought to Black Mesa in 1.0 and 1.5, such as unnecessary railroading, insultingly excessive handholding, questionable balance decisions, and watered-down combat. Since then, it's evolved into an attempt to bring together the best parts of Black Mesa and Half-Life and expand upon them.

Bringing back HL1 setpieces that didn't make the cut for one reason or another, adding incentive for the player to explore and investigate off the beaten trail, trusting players to be able to think and reason their way through puzzles without force-feeding them the answer, expanding upon areas of the facility to make it feel more alive, and making the player have to think about how they fight to survive - that's what BMS Classic aims to do.

Many maps have also received an additional detail pass, making them more atmospheric and immersive by way of enhanced/reworked lighting and improved water visuals. Attempts have also been made to improve performance on some particularly troublesome maps, but given Source's limitations, there's only so much that can be done.


It depends. Other chapter mods, such as the Chapter Overhaul mods or VOX Restoration mods, aren't compatible. BMSC extensively edits many of the game's maps, so any other mods that edit maps are going to run into conflicts. Compatibility with some of these mods (namely the VOX Restoration mods and Black Mesa Character Expansion) is something I'd like to investigate further down the line.


BMSC is primarily a joint effort, between Vassago Rain and myself. Some chapters also have additional support or resources from other modders, as listed in the Contributors section.

It's important to note that BMSC is fundamentally a two-man effort. There's only so much we have the time, resources, and ability to do. As such, we've had to make decisions about what does or doesn't get added/changed. We're just two people with a love for Half-Life doing what we can here, to try and realize Black Mesa's full potential. If you have specific questions about why certain changes were made, or why things were added/removed/etc., feel free to ask.


This download is the BMSC 2.0 edition of Office Complex. The primary change carried over from earlier versions of BMSC is removing the shotgun and putting the revolver back in its place, as in earlier versions of Black Mesa - with the game's weapon balance changes, the shotgun is far too overpowered for OC, significantly detracting from the survival-horror atmosphere it's clearly intended to have.

On top of that, ammo/resources and enemy placement have been refined, to encourage resource management and exploration. You'll have to explore your surroundings to find ammunition and supplies to stay alive. Numerous areas throughout the chapter have also been tweaked to resemble their Half-Life counterparts - from crates in the hallway leading to the guard's armoury, to the Vortigaunt office on map B, to the final stairwell on C, the end result is much more faithful to the original.

Lighting and atmosphere has also been overhauled, as well as some texture work, to make it resemble the original Half-Life iteration better. NPC behaviours have also been refined - ActBusy routines for NPCs to perform, improved reactions and restoring some unused dialogue, allowing the freezer scientist to follow the player (you'll have to bring her to the end as well for the Our Brains And Your Brawn achievement now), and so on.

One of the more significant flow changes I'd like to highlight is moving the B-to-C transition from the bottom of the stairs to the top. This has a significant impact on the gameplay pacing, simply because you aren't carefully dodging a level change trigger (or going back and forth through it multiple times) to get NPCs to follow you upstairs. While it's a relatively minor change, it makes the pacing feel much, much better, with less pausing for level loading.

A more detailed changelog can be found in the Workshop download folder - for this addon, that'll be somewhere like Steam/steamapps/workshop/content/362980/3032364338. The contents of the changelog can also be found in the pinned discussions.