Before the release Deus Ex, there were features that were removed from the final product. These changes range from deleted vehicles and player skins to the removal of entire characters and mission strands.
The initial idea of Deus Ex was originated by Warren Spector in 1994 while he was working for Origin Systems. His original conception of what would become Deus Ex was entitled Troubleshooter. After finishing development of System Shock, Spector had tired of straight fantasy and science fiction and he "got obsessed with this sort of millennial weirdness" leading to the conspiracy-focused storyline for the game. He stated in April 2007 to PC Zone magazine:
- I was a huge believer in the 'immersive simulation' game style, exemplified by games like Ultima Underworld, and I wanted to push the limits of that sort of game further. But I could never get the project off the ground at Origin or, later, at Looking Glass. (I think it was lack of interest at Origin/EA and it was mostly a lack of money at LG!) But then John Romero and Ion Storm came along and said, 'Make the game of your dreams. No limits.' It took me about two nanoseconds to say 'Yes!'
The title "Deus Ex" is derived from the Latin expression deus ex machina, literally meaning "god out of the machine". It is used in drama and literature to describe an outside force that suddenly solves the seemingly unsolvable problem(s) the characters face in an extremely unlikely or impossible way. Warren Spector, executive producer for Deus Ex, has stated the name was both meant as a reference to the various factions in the game who aspire to god-like powers, as well as a dig at the typical video game plot, which tends to be laden with "deus ex machina" artifices and other poor script writing techniques. The meaning of the "JC" initials in the protagonist's codename, JC Denton, is unclear and never referenced in the story. Harvey Smith, lead designer for Deus Ex, has stated that originally JC was supposed to be a descendant of Jesus Christ. However, Warren Spector has said the name "JC" was chosen for its unisex qualities when the developers were still planning to let the player choose the gender of the main character. This feature was later implemented into the game's first sequel, Deus Ex: Invisible War, where the player plays as 'Alex D' who can be either male or female. During sections of the game where the New York skyline is visible in the background, the two towers of the World Trade Center are noticeably missing; the real towers were destroyed a year after the game was released. Harvey Smith has explained that due to texture memory limitations, the portion of the skyline with the twin towers exists in the game's data files but had to be left out of the final game, with the other half mirrored in place of it. According to Smith, during the game's development, the developers justified the lack of the towers by stating that terrorists had destroyed the World Trade Center earlier in the game's storyline. Warren Spector however states "I wish we could say that we did it on purpose and we were sort of seeing the future. But it was actually just a mistake. The artist who did the skybox just uh, left them out. And it sort of worked out in an unfortunate way." There was also a forth ending planned in Area 51 which involved JC siding with Bob Page, who offers him a major continent in exchange for letting him merge with the Helios AI, but this was scrapped due to time constraints.
Originally 25 missions were planned in 16 localizations.
- Hong Kong
- Tokio - Disneyland (underwater)
- New York City - Liberty Island, Manhattan, Central Park, Belvedere Castle
- Washington - White House, intended to be the location of the final battle with Walton Simons.
- San Antonio
- New Orleans
- Los Angeles (underwater)
- Vandenberg Air Force Base
- Nuclear Silo
- London - subway station.
- Russia - Siberia
- Taj Mahal
- Space and the Moon
- Area 51 - Final
The beta version had three additional skills; brawling, communication, and stealth. The brawling skills states it is "USED FOR FIGHTING WITH HAND WEAPONS --------------------".
The communication skill would be used to enable extra choices at higher levels, the code for this check still exists in the ConEdit program. ConEdit also displays skill levels as Novice, Intermedia, Advanced, Master, rather than the final Untrained, Trained, Advanced, Master.
There is no information on the stealth skill.
Unreleased Version 1.000fEdit
An unreleased version dated Sunday, June 4th, 2000, 12:57:34 exists, with multiple changes compared to the first publicly released version, 1.002f, dated Wednesday, June 7th, 2000, 10:20:10.
- The stealth pistol allows recoil weapon mods to be applied to it. This was likely changed as the stealth pistol has virtually no recoil.
- The plasma rifle plasma has a more detailed effect while flying, this was probably reduced as it was more taxing on systems at the time.
- Using a Fire extinguisher does not automatically extinguish the player, the player must be hit by the halon gas to be extinguished.
- Changing level does not automatically extinguish the player, going back to the level where you were on fire makes you continue to burn, with the fire effect displaced in the location where you changed level.
- Running out of energy mistakenly displays a debug message in the message log.
- Placing a grenade on a wall doesn't update the amount of grenades you have on your belt.
- Looting a body deletes the items they contain if the player doesn't have room to pick them up, losing them forever. In the final version, items are only deleted if you have a copy of the item in your inventory.
- The game counts the player as helping at Osgood and Sons Imports in Hell's Kitchen if no terrorists are conscious and there are at least three that were knocked out by the player or killed by NPCs, killing does not count. In the final version, the player is only counted as helping if three or more terrorists were killed by the player with non-explosive weapons.
- The UNATCO troopers outside the 'Ton Hotel are slightly broken, talking to the trooper on the right makes the left one talk.
- In the Battery Park subway, the male hostage always talks, if he is dead it is impossible to tell the female hostage to escape.
- The music browser in the legend menu was more crude, displaying file names for each track rather than neater names.
- Skills are sorted alphabetically, like in the E3 footage, in the final version this was changed to have weapon skills at the top.
- Chairs in Hong Kong have a slightly different sitpoint, causing NPC legs to clip through.
- Minor controls for volume and tremor were add to the dance music in the final version, it doesn't make a noticeable difference.
- When asking Harley Filben who Juan Lebedev buys off, JC's inflection is different, stressing "Who does he buy off?" this was changed in the final version to be more general.
- The 'UNATCO and the Future' datacube has the text '[Document filtered per UNATCO Terror Monitoring Act 919-05 Sec. IV]' missing.
- Jock's infolink at the start of chapter 4 is different: "Your brother's hurt pretty bad. You'll find him at the apartment." vs the final "Your brother's hurt pretty bad. You'll find him at the apartment. If he can walk, get him to come with you. I can pick you guys up in Battery Park.". It is extremely likely that at one point you were meant to start in Battery Park, as other cut lines for UNATCO troopers exist in the final version, intended to be used at the dock and outside Castle Clinton.
- During the escape from the Liberty Island MJ12 lab, the conversation with Paul Denton is different, with a doctor talking and mentioning that he (the doctor) has arranged for escape from the island, using your own escape as a distraction. This was likely cut because the conversation is important and required for the player to progress, which could be prevented if the doctor was too far away.
- The Men in Black standing outside UNATCO Headquarters who tell the player about Walton Simons and his interrogations have a different voice, either a placeholder or without the MiB voice effect applied. One line is also different, with the final version being: "The prisoners on Level 3 are a sensitive matter. Leave the interrogations to Mr. Simons. You are authorized to receive your orders from Joseph Manderley, after which you will return to the helipad." while the beta has: "Mr. Simons will conduct the interrogations, that will you free to get your orders and return immediately to the helipad.", both versions have the same subtitles however.
- The Man in Black at Vandenberg Air Force Base does not have their voice effect applied, sounding like normal a person.
- The Infolinks at the Pasadena Ocean Lab don't have as much static applied to them.
- The Men in Black at the Hong Kong VersaLife facility and the cut MiB conversation at the Area 51 hangar have quieter voices.
- Two Woman in Black lines have no voice effect applied to them.
- Alexander Brandon is credited for the role as Jimmy in the final version, while the beta credits Kris Nevins, who is not mentioned in the final credits at all and is likely the brother of Will Nevins who voices other characters. Kimberli Daniels also has a typo in her name.