History Trivia / BlackMesa

** A cut radio conversation for "Surface Tension" still exists in the files -- specifically, it would have featured one of the snipers who takes aim at Gordon as he emerges onto a rooftop on the penultimate level, who would have requested permission from his superior to open fire and confirm Gordon's identity saying he "looks like an orange ice pop" in his HEV suit.

** The effect of blood and Bullsquid acid staining Gordon's arms and weapons, while used in the mod release, is disabled by default in the retail release due to an unresolved lag hitch that occurs when the effect is first applied. It can be re-enabled with the console command '''cl_mdldetailfx_enable 1''', however.

** An updated version of the ''Half-Life'' HD Pack's M4 assault rifle was to be able to be used in place of the [=MP5=] via a console command. The weapon was cut altogether for unknown reasons, but several mods exist which implement is as a reskin for the [=MP5=], such as the [[http://blackmesa.gamebanana.com/skins/126786 Animation Revamp]] mod.

** In April of 2021, the devs released [[https://steamcommunity.com/sharedfiles/filedetails/?id=2463740880 The Xen Museum]] to the Steam Workshop, showcasing earlier, discarded builds for the various maps of Xen. One notable change from the developer builds to the finished product is that the Vortigaunts/Alien Slaves would have [[AlwaysChaoticEvil almost always been hostile to the player]], even in Xen. In the finished product, the Vortigaunts in Xen are only hostile while under the influence of an Alien Controller and assist Gordon in several parts. The Museum also includes prototypes of sections cut entirely from the game, such as a mining area in "Interloper".

** There's also the cancelled ''Hazard Team'', which was meant to be a Source remake for the UsefulNotes/PlayStation2 version's co-op mode, ''Decay''.

* DescendedCreator: Kala Nielsen, the spouse of composer Joel Nielsen, provides the OneWomanWail of the Xen soundtrack.

* ActingForTwo: Kevin Sisk, who is mostly known as the voice actor of the security guards, also lends his voice to a scientist in "Anomalous Materials", Eli Vance, the Nihilanth, the Vortigaunts, the G-Man, [[CrossdressingVoices the HEV Suit]], and the ''[=MP5=]'s grenade launcher''.

** An updated version of the ''Half-Life'' HD Pack's M4 assault rifle was to be able to be used in place of the [=MP5=] via a console command. This was skinned and modelled but was cut for unknown reasons. It's available as part of the [[http://blackmesa.gamebanana.com/skins/126786 mod Animation Revamp]] mod, alongside the HD M9 pistol.

** Magnusson originally planned to make a cameo appearance as one of the scientists in the room overlooking where Gordon meets with Eli and Kleiner.

* ActorSharedBackground: The consultant and voice actor for the HECU, Michael "Mikee" Tsarouhas, is a former Marine. He was also the artistic director and voice actor for ''VideoGame/{{Insurgency}}'', which itself started out as a Source engine total-conversion.

* CutSong: Several songs from the game's OST are included in the files despite not being used in the game proper, including the [[https://www.youtube.com/watch?v=u7p9t9J-2pE Black Mesa Theme]] and [[https://www.youtube.com/watch?v=zFTqQ2r2c3Q its remixed version]], [[https://www.youtube.com/watch?v=A8C1--DLHcA Blast Pit 2]], and [[https://www.youtube.com/watch?v=ZOHMU8ZKO2E Unforeseen Consequences]].[[note]]The remixed Black Mesa Theme and Unforeseen Consequences were actually used in the mod version of the game but were replaced by new compositions in the retail release.[[/note]]

** The security guard who berates the lack of a ponytail on Gordon. This detail was taken out during the mod's development when it became unnecessary for an actual player model, being part of Gordon's ''Half-Life'' model down to his original concept in the very early stages of ''Half-Life'''s development (a very hairy Viking-like man nicknamed "Ivan the Space Biker"). Also, the third-person NPC of Gordon seen in ''Opposing Force'' sports a ponytail and sunglasses.

* DevelopmentHell: The game started development in 2004 and was originally set for release in 2009. Instead, it got delayed until late 2012. Even then, the Xen levels weren't completed in time for that, and we wouldn't get so much as a tech demo of them until mid-''2019''. This is somewhat justified considering it's made by volunteers in their spare time, and when you do the math, [[https://i.imgur.com/ZXWXi.jpg actually took around the same amount of man hours as your average game.]]

* InspirationForTheWork: In 2004, Valve did a semi-remake of the first ''Half-Life'' game by upgrading it to the Source engine. The remake received mixed reviews, particularly for not really upgrading the graphics or presentation of the game and introducing a number of glitches, in return for ragdoll physics on corpses and more realistic water. Gabe Newell later stated that a FanRemake was "not only possible... but inevitable". This caused two separate development teams to start working on similar projects, which eventually led to the two groups teaming up.

** A number of users from the Black Mesa web forum who were participating in attempting to solve the Alternate Reality Game received an in-game shoutout on one of the whiteboards in Xen.

** Cockroaches were meant to have AI and 3D models as they did in the first game. They were simplified to a particle effect as a means of optimization since the game's graphics were already pushing the Source engine to its limits.

** HECU soldiers were once programmed so that they would eventually run out of ammo for their primary weapon, forcing them to switch to using their sidearm. This was cut after playtesting revealed that players could easily exploit this behavior by hanging back and [[VictoryByEndurance waiting for the soldiers to expend their ammo]] before confronting them. They were originally also able to [[GrenadeHotPotato throw the player's grenades back at them]], which didn't make the cut due to problems with "realistic implementation".
** In April of 2021, the devs released [[https://steamcommunity.com/sharedfiles/filedetails/?id=2463740880 The Xen Museum]] to the Steam Workshop, showcasing earlier, discarded builds for the various maps of Xen. One notable change from the developer builds to the finished product is that the Vortigaunts/Alien Slaves would have [[AlwaysChaoticEvil almost always been hostile to the player]], even in Xen. In the finished product, the Vortigaunts in Xen are only hostile while under the influence of an Alien Controller and actually assist Gordon in several parts. The Museum also includes prototypes of sections cut entirely from the game, such as a mining area in "Interloper".

** Several characters and conversations were cut from "Anomalous Materials" in order to keep the chapter's pacing from becoming too slow, including a trio known as [[https://youtu.be/5q20OlFDTi4 the "Always Laughing About Something" scientists]]. Additionally, the scene where a {{jerkass}} scientist in the Development Lab demands his co-worker make coffee for him was meant to end with said co-worker actually preparing the coffee... but not without [[ToiletHumour going to the bathroom and urinating in the mug first]].

** Text strings hinting toward a PvE zombie mode for Deathmatch can be found in the game files, though no such playable mode actually exists.

** The big ambush at the end of "Questionable Ethics" went through several iterations during development, with additional elements such as a LAV bursting through the front of the lobby given consideration.

** The guard who opens the way to the Lambda Complex in "Surface Tension" was once meant to be able to follow you into the next level, instead of being killed off-screen by an Alien Grunt. As evidenced by some leftovers in the sound scripts, he would have had some things to say when coming across the HECU triage camp and could react to the radio transmission that can be heard there.
** Magnusson was originally planned to make a cameo appearance as one of the scientists in the room overlooking where Gordon meets with Eli and Kleiner.

** The Nihilanth's tower is actually a living organism if all of the OrganicTechnology wasn't a big enough hint.

** A disabled feature in the game would have [[https://youtu.be/8lhuGjyiGOI forced the player to fight off headcrabs attempting to "couple" with their head]] by [[SmashingSurvival rapidly tapping the attack button]]. This feature can still be enabled with a console command in the mod version but lacks the proper textures, though [[https://gamebanana.com/textures/3497 there's a mod to restore them.]]

** ''[[https://store.steampowered.com/app/311810/Operation_Black_Mesa/ Operation: Black Mesa]]'' by [=TripMine=] Studios, a Source remake of the Creator/GearboxSoftware expansion packs ''VideoGame/HalfLifeOpposingForce'' & ''VideoGame/HalfLifeBlueShift''[[note]]''Operation: Black Mesa'' was the original name for the ''Opposing Force'' portion of the project, with the ''Blue Shift'' portion originally being developed as a semi-separate project under the title ''Guard Duty''[[/note]]. Despite the similar title, the game does not share assets with Black Mesa, though it is in a similar state of DevelopmentHell as of writing.

* FollowTheLeader: ''[[https://store.steampowered.com/app/311810/Operation_Black_Mesa/ Operation: Black Mesa]]'' by [=TripMine=] Studios, a Source remake of the Creator/GearboxSoftware expansion packs ''VideoGame/HalfLifeOpposingForce'' & ''VideoGame/HalfLifeBlueShift''[[note]]''Operation: Black Mesa'' was the original name for the ''Opposing Force'' portion of the project, with the ''Blue Shift'' portion originally being developed as a semi-separate project under the title ''Guard Duty''[[/note]]. Despite the similar title, the game does not share assets with Black Mesa, though it is in a similar state of DevelopmentHell as of writing.

* ScrewedByTheLawyers: Averted. Valve only had two stipulations in regards to ''Black Mesa'' getting onto Steam:
## The development team had to remove the word "Source" from the title so that people didn't think it was an official Valve release.
## Valve got first dibs on playing the game.

* TheWikiRule: [[https://web.archive.org/web/20160831175033/http://wiki.blackmesasource.com/Main_Page Had a wiki hosted on the official website]], which has since gone offline for unclear reasons.

** [[https://steamcommunity.com/sharedfiles/filedetails/?id=2068862348 Black Mesa Character Expansion]] by jazze. BMCE is an NPC overhaul mod that expands & enhances Black Mesa's humanoid [=NPCs=], increasing the visual variety of Scientists, Security Guards, HECU Marines & Zombies, as well as introducing additional Black Mesa staff types (office/maintenance/cafeteria workers, engineers, custodians, paramedics and firemen) & overhauling the Face Creation system.