Doom press release beta

The Doom press release beta, the final pre-release build of the game to be distributed externally, was released on October 4, 1993. It was intended for use by journalists to allow them to trial the game before its release. The beta is time sensitive and will not start if the DOS system time is later than October 31, 1993. A utility created by Lee Killough is bundled with the public release on the idgames archive which locks the system time into range while it is resident in memory, allowing play to proceed. It also has a "password", requiring the user to add the command line parameter when starting the game.

Differences
While the press release beta is in many regards similar to the completed releases of Doom, there are various differences with the finished game.
 * The player has a counter for his remaining amount of lives by the status bar face, and an additional life is added each time a soul sphere is picked up. However, the counter is bugged and the number graphic is obscured by the mug sprite. It also does not decrease if the player dies.
 * If the player dies, the game becomes paused, and the viewpoint immediately switches to floor-level instead of decreasing gradually. The player's weapon also does not lower, and the screen remains tinted with the red flash caused by the final blow.
 * Messages are displayed on the right side of the status bar, replacing everything but the ammo for the current weapon and the health percentage, for a couple of seconds or so. The messages use a small yellow font and three lines can be displayed at once.
 * The game keeps score, and adds points for killing monsters. The current score can be viewed in the automap.
 * There is no ARMS or FRAG panel on the status bar; an ITEM panel in its place keeps track of the number of demonic items collected instead. The weapons currently owned appear on the status bar when viewing the automap, they are represented by their pickup sprites rather than numbers.
 * The end of the chaingun muzzle is hidden by the circular plate before it.
 * The rocket launcher fires slower, recoiling after each shot.
 * The plasma gun is slightly different and fires alternating green and red bursts. The first shot is always a green projectile, and both projectiles have different travel speeds, with the red ones being faster.
 * The BFG fires the same projectiles as the plasma gun. However, each call of its attack function fires both a green and red projectile while spending one cell. This function is called 40 times, for a total of 80 projectiles at a total cost of 40 cells. The projectiles have slight horizontal spread, and plenty vertical spread, and they can bounce off floors and ceilings. The BFG will refuse to fire and will automatically switch out if the player has less than 40 cells.
 * Imps throw the red plasma balls fired by the beta plasma gun, albeit with a slower travel speed.
 * The lost soul is gray and has alternating yellow and blue energy around the skull instead of flames. They attack from afar with an invisible and unavoidable hitscan effect rather than a charging attack. When killed, this lost soul dies in a green explosion, leaving behind a floating pile of bones.
 * The baron of Hell's projectiles use a different sprite instead of the one used in the release version, because the BAL7 sprites intended to be used by its attack are erroneously named, causing the rotations to be erratic. The sprites used for its attack in this version were later reused as a part of the arachnotron's plasma attack's explosion in Doom II.
 * Many other sprites not mentioned here are different in appearance.
 * Lifts are much slower than in the finished game, having the same speed as perpetual lifts in the final release.
 * The ouch face appears whenever the player walks on a damaging floor.
 * The light amplification visor uses a green colormap, which imitates night vision goggles. This suffers from the same bug as the invulnerability colormap in the release version. This powerup does not wear out after being collected.
 * The partial invisibility effect uses the inverse black and white colormap reserved for invulnerability in the finished game.
 * Invulnerability does not use a colormap and the radiation shielding suit does not tint the screen green.
 * The player cannot gib monsters, and monsters that die under a moving ceiling (like a door) cannot be crushed into a pool of blood.
 * Non-solid actors are detected as solid by moving ceilings. This causes the moving ceiling to act as if an actor is still in the way, causing doors to reopen if a monster dies under it, and crushers to slow down as if a monster or player was caught underneath.
 * Monsters of the same species cannot hurt each other with projectiles, because projectiles simply pass through, rather than colliding.
 * Monsters with the ambush flag completely ignore the player's gunshot sounds.
 * Collission detection is very buggy, which causes player weapons to sometimes fail to hit any targets at all.
 * The chainsaw's idle frames do not animate.
 * Although there are multiple sky graphics, the sky used in all levels is black over a low range of light brown mountains. A portion of this sky is eventually used as the F_SKY1 placeholder flat used to assign a sky texture as the ceiling to a sector during design.
 * Though DMX is present in the executable, and there is basic programming for sound effects and music, both are deliberately disabled at startup for this build. It is likely that the then-current behaviors, such as lack of sound attenuation and a limit of one sound playing at a time, were already intended only as interim and that id wanted to prevent reviewers from getting a bad impression.



Demonic items
This release of Doom still contains the demonic items described in the Doom Bible. Collecting 50 of them grants the player an extra life.
 * Demonic dagger. It has a skull on its hilt, appears to be two-bladed, and seems to be driven into the ground. Its description in the Doom Bible is: Also used in sacrifices, this knife is black and red.
 * Skull chest.
 * Unholy bible. Brown, open book on a pedestal. Described in the Doom Bible as Found only in Hell, this is a tome of great evil and holds some knowledge of the ways of demons (if studied for awhile-i.e. player doesn't have time to use knowledge). Well-guarded.
 * Evil Sceptre.

Cheats
Several cheats were included with the documentation for the beta:


 * tst: Behaves similar to the iddqd cheat (God mode)
 * eek: Behaves similar to the iddt cheat (displays entire map)
 * amo: Behaves similar to the idkfa</tt> cheat (gives all weapons, ammo and keys)
 * nc</tt> or noc</tt>: Behaves similar to the idspispopd</tt> cheat (no clipping mode)

Levels
Three levels are included.

Demo Map 1: E1M2. The room with the walkway over slime in the final is more of a twisting maze in this version, the outside area lacks a chaingun, elevators are used in many places instead of stairs, and the secret area with the backpack in the computer maze has not been added.

Demo Map 2: E3M5. There is no BFG9000, but is otherwise complete.

Demo Map 3: E2M2. It lacks a berserk pack, the area past the warehouse and main hall uses demonic textures instead of the techbase ones used in the final version, and the room with the chainsaw has a box of shells instead of the chainsaw.

Demo Map 2 is internally referred to as E2M5 and Demo Map 3 is E3M2, because at this point in development, the episode progression was still "Base" -> "Hell" -> "Corrupted Base" as laid out in the Doom Bible.

Download
The press release beta can be played in DOSBox. The version uploaded at the idgames archive includes the fakedate</tt> terminate-and-stay-resident utility by Lee Killough, which sets the DOS system date permanently to 10/31/1993 for as long as it remains loaded in memory.

After downloading, follow the steps listed here:
 * 1) Extract the zip file inside your normal operating system.
 * 2) Inside DOSBox, use the mount</tt> command to bind the directory you unzipped it in to a drive letter.
 * 3) Run install.bat
 * 4) Input a drive and directory path (relative to DOSBox's mounted drives) where you want the press release files to install.
 * 5) Exit DOSBox and extract the fakedate</tt> archive into the location where you installed the press release.
 * 6) Return to DOSBox and run the following commands in order:
 * 7) fakedate</tt>
 * 8) newdoom -pressrelease</tt>

Technical

 * A number of empty lumps (I-WEAPON, I-AMMO, etc.) are found between the ICON_STA and ICON_END markers.
 * The COLORS12 and COLORS15 lumps are still there. DOOMERR and HUFONT have been removed, though.
 * Sneas have mostly disappeared, only the TITLEPIC remains in this format, unchanged since the alpha 0.4. It still uses its own palette called TITLEPAL. However, two extra null bytes have been appended to the TITLEPIC lump, maybe to pad it to a multiple of four.
 * All other graphics are now either flats or in a modified picture format. The latter is slightly different from both its final and its earlier version. Other than the header size change, they are also padded with 00 after the end of the last column to arrive at a byte size that is a multiple of four.
 * The map format is nearly definitive, missing only the REJECT lump; it is possible to load them directly in ports which tolerate missing REJECT lumps. Maps are still between M_START and M_END markers.
 * Many graphics are now outside of markers, notably most of those related to the status bar and the menu. The mugshot graphics are between FACES_ST and FACES_EN markers, and the L_ markers keep the TITLEPIC and its TITLEPAL, and all the intermission graphics (WI*).
 * The COLORMAP reached its final size of 34 maps. All the colors in the PLAYPAL are now definitive, and it now holds 13 palettes: palette 1 is normal, 2 to 9 are progressively redder, 10 to 13 are progressively brighter.
 * Lost souls and cacodemons do not have the ability to float in the air, and their sprites are given extra vertical offsets to compensate. Cacodemon sprites lack some of the rotations. Explosive barrel sprites are also present in the IWAD, but none appear in-game.

Trivia

 * Remnants of the "message window" code remain in the Doom source release, although this is limited to only a few "#define" C constants and several variables, some of which are still uselessly manipulated in the functions and  (most of the actual code is not present).
 * Although the BFG9000 is fully implemented and usable, it cannot be obtained without cheating. Despite this, there is a string associated with its pickup in the executable, that reads "You got the BFG9000! Oh, yes.".
 * If the player uses the ammo cheat, the cheat gives 200% armor, but does not absorb damage.
 * This build predates the A Visit to id Software video by less than a month, but the amount of changes between it and the build seen in that video are still dramatic.