Quake

Quake is the story about a homicidal man that likes to kill Lovecraft-inspired monsters through barely connected level sets. He also likes to murder his friends (who respawn as soon as they are killed) in castles that have a large Jesus crucified in them for some reason.

The main game doesn't have a lot of unused stuff, but there's a shitload of it in the two prototypes floating around.

Unused “Sell” Screen
A poorly-made screen that was supposed to urge you to purchase the final version can be found hidden in the game's sprites. There is no way to bring it up in the game, making it unused. This message appears in the Beta3 prototype and is unused there as well.

Unused particle effect
Each entity is given an .effects field to control entity-specific lighting. As spotted in defs.qc, an unused flag EF_BRIGHTFIELD appears, but is never used elsewhere in the QuakeC sourcecode.

If set, it creates yellow glowing dots surrounding a given entity in question. In GLQuake, they appear as circular dots, while non-GL versions render them as solid block pixels.

Unused lighting effect
defs.qc also defines EF_BRIGHTLIGHT. This causes an entity or object to illuminate a bright light.

Aside from illuminating a wider area, it is otherwise identical to EF_DIMLIGHT (which is the standard glow for quad damage or pentagram of protection).

Unused sound effects
Two unused sounds exist in the sound/boss2/ directory that are never heard as there is no code to play them. The unused sounds are idle.wav and sight.wav, which would be for Shub Niggurath's idle and sight sound. Interestingly, they are still precached on loading the end level, which is how it was included by accident as id's PAK building tools include every file referenced in the precache functions by the QuakeC code.

Similarily, sound/hknight/grunt.wav is also unused and still precached.

Unused text
There is text in the game that is unused:


 * "Satan's power deflects 's telefrag" was meant to be used if someone tries telefragging an invincible player, but it never appears in normal play. This is fixed in QuakeWorld, as well as a community mod.
 * " was fried by a Dragon" - a client obituary for a dragon, not implemented in Normal Quake. The text is replaced in the expansion pack Dissolution of Eternity, where the dragon is actually implemented.
 * " became one with Shub-Niggurath". While this boss appears, it has no attack.  The only way to be harmed by it is to approach it, and it is credited to a generic trigger rather than Shub-Niggurath.
 * " was vomited on by a Vomitus". This monster was never implemented.

Other unused content

 * The quake console provides "+use" as a command. The game doesn't use it (with the player shooting or touching items instead), and modders were unable to exploit it until the source code was fixed.
 * Quake incorrectly claims that it has unused content on a level - Rotfish are counted twice as part of the total number of monsters in a level.
 * Quake, starting with version 1.06, has two copies of progs.dat in pak0.pak. The unused version (CRC 51103; used in version 1.01) is found at $580358, is 410616 bytes long, and is not indexed.  The version in use (CRC 24778) is found at offset $116df17 and continues to the end of the file.   The index entry for the newer progs.dat file also contains semi-random characters to prevent triggering the anti-modding mechanism in the Shareware version.

Map specific content

 * START has an unused teleport beneath the exit to the END map. Attempting to enter it by using noclip will stop the same and place you at the console, because it has no corresponding exit.
 * When playing E2M3 as a deathmatch level, an item at coordinates '-1200 208 -106' falls out of the level, meaning Quake itself auto-cuts it from the map. It's a super nailgun, and is already close to another super nailgun that doesn't fall out.
 * Also in E2M3, when playing in deathmatch, there is an untextured button that appears by the Super Nailgun.
 * E2M4 has a few monsters that will not teleport into the active map area.
 * E4M3 has a fiend that is spawned in easy, but not the corresponding teleport.
 * E4M5 has an unused teleport gate above the secret exit, and it can be reached by a grenade jump. It has no corresponding exit and will dump you to the console.
 * E4M8 has an unused teleport above the start, reachable by a grenade jump. It teleports you to the console.


 * HIP2M4 - two spikemines are missing on hard difficulty. They are placed too close to the walls.
 * HIP2M5 - three spikemines don't teleport into the map.
 * HIPDM1 - a spikemine is reported to be present, but is missing. (The missing monster also registeres as a monster during deathmatch).
 * R1M4 - a shambler entity "t399" is spawned in all skill levels, but on easy/normal, the corresponding teleport isn't.
 * R1M6 - A wraith will not enter the map.

Brown faded menu background
Version 1.07 (first included with Scourge of Armagon) and all subsequent versions removes the brown fade effect in the menu that was present in all versions before it. The reason may involve an intense video memory access slowdown for the fade lookup when the engine was being ported to Windows using Scitech MGL and it was faster to write a black pixel pattern to the video buffer instead of reading every pixel from the video memory.

The only trace left of the fadescreen code left in the released GPL source was only recently discovered as a dummied out "gelmap" table that was going to be used as a feature to color models to a single range of colors, but was scrapped.