Aliens TC

Aliens TC is a total conversion based on the movie Aliens, created in 1994 by Justin Fisher.

It was the first total conversion and is one of the most famous. In the week following the release of Doom II, there was more discussion in the Doom newsgroups related to Aliens TC than Doom II. The popularity of the Aliens TC even reached outside the Doom community, for instance providing inspiration for the 1998 Dreamworks game Trespasser. Fisher was offered employment by various game developers (including Dreamworks for the team that would later make Trespasser), but declined in order to finish his university degree.

The Aliens TC is noted for its suspenseful atmosphere. The first level is devoid of enemies, a surprising feature considering the fast-paced action of Doom. Later on, however, the players faces the aliens and even gets to use the powerloader from Aliens as a weapon.

Fisher had gotten the idea to create the Aliens TC within his first five minutes of playing Doom in late December 1993, noting the similarity in atmosphere of Doom and the movie. Incidentally, it has later become known that id Software originally planned to base Doom on an Aliens license, but abandoned the idea in the early stages of development in order to retain creative freedom.

There was also an attempt to make a Aliens total conversion mod using the Quake engine, but 20th Century Fox owned the rights and sold them to Sierra Entertainment to make the Aliens versus Predator for the PC, finally released in 1999.

Levels
The original mod was for Doom 1.666 and had to be patched over the game, replacing the second episode The Shores of Hell. It turned out to be an excellent choice, as the music tracks well complemented the level's atmosphere; especially from E2M2 and E2M6, when the Marines first enter the Atmospheric Processor, and when Ripley returns there to search for Newt, respectively. Fisher later adapted Aliens TC for Doom II.

Most of the textures are techbase. The background uses Knee Deep in the Dead's misty, mountainous skyline. Fisher also cleverly used hellish textures, colouring them green, which made it look convincingly like wall slime.

E2M5 and E3M1 are designed for deathmatch, as they have proximity indicators that lower and flash when a player walks by. Most of the levels, however, are generally non-linear with the exception of E2M3 (sealing off the MedLabs and getting to the transmitter).

"Escape from the MedLabs" was split up into E2M4 and E3M1, the later being a bonus level. E3M2 (the Alien Ship) is another bonus level which was made by Fisher's friend Richard Love.

Aliens
The "regular" aliens are based off of the Demons and take approximately 2 shotgun shells or 14 bullets to bring down. This was a key reason why AliensTC was difficult, as it took much (scarce) ammunition to kill these common enemies, which could run fast and could do significant melee damage.

Aliens that spit acid use Imps. While no member of the species so in the actual Aliens universe, Fisher said he wanted to add variety.

Aliens that explode and release corrosive acid were made by using a Spectre and exploding barrel, which several reviewers considered very innovative. Consequently, there are no regular exploding barrels in the TC. The only clue that an Alien would burst is that it makes no sound.

To implement the hatching eggs that release face huggers, Fisher had the Cacodemon release a Sergeant, not unlike how the Doom II Pain Element releases Lost Souls.

The Queen Alien (based on the Cyberdemon) graphic was a poorly digitized version of a model, as Fisher conceded.

Weapons

 * 1. Fists
 * 1. Power Loader - based off the Chainsaw
 * 2. Pistol
 * 3. Shotgun
 * 4. Pulse Rifle - uses the Chaingun
 * 5. Grenade Launcher - Rocket launcher
 * 6. Smartgun - Plasma Rifle

The Grenade launcher is underslung on Pulse Rifle, so both weapons are acquired with one pickup. Fisher designed Weapon #7 to punish cheaters, so it will simply show images of the Power Loader but not do anything.

While the Pulse Rifle was the most common weapon in Aliens (1986), the shotgun tends to be the most widely used in Aliens TC due to the availability of shells, though the shotgun only makes one appearance in the movie.