Doom 64

Doom 64, released on March 31, 1997 for the Nintendo 64, is a spin-off. The game has all new graphics and runs with a modified version of the Doom engine. Doom 64 was released by Midway, in cooperation with id Software.

The plot focuses on events in a non-canon story which plays no part in the original games of the series. An evil entity known as the Mother Demon has survived and brought back the decaying dead creatures you once killed. It is up to you, the lone unnamed space marine, to stop the legions once again.



Story
Quoted from the Doom 64 manual:

"Your fatigue was enormous, the price for encountering pure evil. Hell was a place no mortal was meant to experience. Stupid military doctors: their tests and treatments, were of little help. In the end, what did it matter - it was all classified and sealed. The nightmares continued. Demons, so many Demons; relentless, pouring through.

Far Away...

The planetary policy was clear. An absolute quarantine was guaranteed by apocalyptic levels of radiation. The empty dark corridors stand motionless, abandoned. The installations sealed.

The Present...

A long forgotten relay satellite barely executing, decayed by years of bombarding neutrons, activates and sends its final message to Earth. The satellites message was horrific, from the planetary void there came energy signatures unlike anything sampled before.

The classified archives are opened. The military episodes code named "DOOM" were not actually completed. A single entity with vast rejuvenation powers, masked by the extreme radiation levels, escaped detection. In its crippled state, it systematically altered decaying dead carnage back into corrupted living tissue.

The mutations are devastating. The Demons have returned even stronger and more vicious than before. As the only experienced survivor of the DOOM episode, your commission is re-activated. Your assignment is clear: MERCILESS EXTERMINATION."

Gameplay developments
Changes were made to the computer Doom engine for use in Doom 64, and gameplay elements were altered. Doom's core gameplay, however remained the same: the exploration of demon-infested corridors, looking for keycards, switches and ultimately the map's exit while surviving deadly traps and ambushes.

Key differences from the computer games in the series include:
 * 32 exclusive new levels
 * New, larger sprites for all enemies, items, weapons and projectiles, created from high-poly rendered models, which were anti-aliased when close to the player to prevent pixelation.
 * New, high-quality sound effects (the same as used in the PlayStation and Saturn versions of Doom).
 * A more horror-based atmosphere than the science fiction-oriented one seen in earlier games, including darker and more foreboding color schemes used to increase a sense of fear in the player.
 * All new textures, scrolling skies, limited room-over-room architecture and more advanced line triggers.
 * Scripted events through macros, such as almost-complete alterations of room structures.
 * Enemies that appear out of thin air after triggering a tripwire or switch.
 * Tripwire booby traps, from darts to homing fireballs.
 * Camera effects
 * More advanced atmospheric colored lighting and effects, such as parallaxing skies, fog, and lightning.
 * A more ambient soundtrack instead of the rock music of past Doom games.
 * More extensive usage of Satanic imagery (pentagrams, inverted crosses, depictions of sacrifice) than the computer version of Doom with differing usages of horror schemes.
 * No commandos, arch-viles, spiderdemons or revenants (perhaps removed due to the limited storage capacity of Nintendo 64 cartridges).
 * The nightmare imp and Mother Demon are introduced as new monsters.
 * The player's viewpoint is from chest level, rather than eye-level, making all objects and characters appear larger in relation to the player.
 * The hell knight and baron of hell can hurt each other with their projectiles, and infight as a result, contrarily to the PC version where there is a hardcoded exception for them.
 * Certain monsters were rebalanced with new behaviors or attack properties (e.g. such as giving the Arachnotron a weaker twin plasma gun instead of a stronger single-barrel one).
 * Re-designed weapons that act more devastating than previous installments of the game series (realistic jostling movements when firing the weapons are also present, including being knocked back a few inches from a fired rocket).

Weapons
All the weapons from the original computer game are present, but redrawn. A new weapon known as the Unmaker or the LaserGun (referenced in-game as "What the !@#%* is this!") has been added. It was first mentioned in the Doom Bible and was planned to be featured in the computer Doom games but never appeared. Its appearance in Doom 64 is its only official appearance, and with the power of three ancient artifacts (known as "Demon Keys" or pentagrams) found in the game, it becomes more powerful by a faster fire rate and a max of three laser beams fired with all three "demon keys". (1st makes Unmaker fire faster, 2nd gives it a second beam, 3rd gives it a third beam).

Weapons include:

Chainsaw, Fist, Pistol, Shotgun, Super Shotgun, Chaingun, Rocket Launcher, Plasma Gun, BFG-9000, and Unmaker. (in order of weapon cycling)

The Demon Keys are also a means to clear MAP28: The Absolution: Each teleporter in the map has a symbol representing each key behind them and if the player has the right key, the corresponding teleporter is disabled, making the battle against the horde of demons that teleport in, easier. Also, when killing the Mother Demon, the Unmaker with all "Demon keys" will kill her very quickly.

Levels
Doom 64 featured 32 original levels:

Monsters
Doom 64 includes the following monsters from Doom and Doom II: Doom 64 also has new monsters, which are:
 * Arachnotron
 * Baron of hell
 * Cacodemon
 * Cyberdemon
 * Demon
 * Hell knight
 * Imp
 * Lost soul
 * Mancubus
 * Pain elemental
 * Shotgun guy
 * Spectre
 * Zombieman
 * Mother Demon
 * Nightmare Imp

Source ports
The following source ports are capable of running Doom 64:
 * Doom64 EX

Doom 64: Absolution TC for Doomsday
Since the release of the Doom source code for the computer games, programmers have created feature-enhanced versions of the computer Doom game in their own source ports. Several fans of Doom 64 decided to work to convert the game's exclusive content to the computer using Doomsday engine. This stand alone mod, built on the 1.7.14 release of Doomsday, titled Doom 64: Absolution, was released in 2003. It included near-identical, albeit limited representations of the original Doom 64 levels game along with some new maps of its own. It appealed to many fans as a way to play through the game on a computer without using emulation. However, one of its authors, Samuel "Kaiser" Villarreal, not being pleased with the feel of the game, started working on a more faithful representation of the console game, which later led the TC to be succeeded by Doom 64 EX.