The game is often considered the successor to the Alien vs Predator game on the Atari Jaguar, and as such is the second game in the Alien vs. Predator franchise. It was followed by two sequels, Aliens versus Predator 2 (2001) and Aliens vs. Predator (2010).
- An unnamed Warrior is the playable Alien character in the game.
- Private Anderson (referred to simply as "Private" in-game) is the playable human character, a Colonial Marine stationed at the Weyland-Yutani research facility built around the Derelict Ship.
- An unnamed Predator is the playable Predator character in the game.
During the game, the three single-player campaigns (Alien, Marine and Predator) are completely independent and unrelated (unlike the three streams in Aliens vs. Predator 2, which intersect at various points, or in Aliens vs. Predator, which take place on the same planet concurrently).
Aside from the 6-level (5 in the case of the Alien) campaigns, each species also has access to several unlockable bonus levels that allow them to play portions of the other species' missions. To allow the more three-dimensional Alien levels to be played, Marine and Predator players are supplied with a jet pack and grappling hook, respectively, for these bonus missions.
The opening cutscene shows a group of Colonial Marines killing an Alien. Afterwards, another Alien wakes up, ready to kill the Marines.
- Temple: The Alien strand of the game begins in the upper levels of a temple. Marines have secured the lower levels of the structure, including the colony's Hive. The player must reach the Hive, sealing off the strange energies that feed the temple and disrupting on-site research labs on the way.
- Escape: The player must leave the Hive and enter an adjacent human facility. As the Marines repeatedly fail to contain or kill the player, they issue a general evacuation order, after which the player must locate and hitch a ride on an evacuating spacecraft (which also carries Xenomorph Eggs).
- Ferarco: The player begins aboard the Ferarco, a space freighter with a (well-armed) crew complement of fifty. The ship's interior is loosely based on that of the Nostromo from the movie Alien; the galley, hypersleep vault, landing-strut chamber, observation bubble and the computer interface room should all be familiar to fans of the Alien series. After the destruction of the interior of the computer interface room, the ship initiates a self destruct procedure and the player must quickly reach the escape shuttle (a plot point once again taken from Alien).
- Gateway: The shuttle reaches Earth orbit and docks with the Gateway Station featured in Aliens. Sensors detect a contaminant, the player, who must act quickly to avoid being sucked into the vacuum of space as airlocks are opened. The player must then traverse the infrastructure of the station (mainly via ventilation ducts), causing a minor power failure along the way. Marines are here, and are more heavily armed than in earlier levels.
- Earthbound: The level begins in Gateway's docking tower. Again primarily using the ventilation system, the player must reach a ship scheduled to depart for Earth. As on previous levels, heavily-armed opposition is encountered. Furthermore, near the end of the level, two Predators make an appearance on Gateway, and the player must kill them to proceed to Earth.
The end cutscene shows the Alien curled up inside a shuttlecraft with Earth, its destination, in view through a porthole.
The opening cutscene shows a Facehugger attached to the player character's face. However, as the facility alarms go off, the player character sits bolt upright in bed and realizes that this was just a nightmare.
- Derelict: The Marine's game takes place ten years after the events of Aliens (although the level's briefing states that the campaign takes place in 2145, which is actually 34 years before the setting of Aliens). The Company has built a research facility around the Derelict Ship from Alien and Aliens, and Marines like you are stationed there in case anything goes wrong, which it does. You're the last person to evacuate, and you must leave your quarters and make your way through the research facility to the derelict ship itself. After taking a lift down to the Pilot's chamber (another familiar area from Alien), you reach the colony supporting the research facility.
- Colony: Once you take an elevator up to the surface, all that separates you from the comparative safety of a heavily-armored APC is the main gate, which won't open. You've got to restore power, then hunt down an engineer's security card, which will allow you to escape. You find the card in a medical facility reminiscent of the med lab in Aliens; in fact, all the corridors and structures in this level are modeled in the same style as the Hadley's Hope colony in Aliens. You get what you came for, open the gate, and run across open terrain toward the APC with Xenomorphs hounding you all the way.
- Invasion: The APC brings you to an Atmosphere Processor (featured in Aliens, although the interior in the game doesn't really resemble the movie sets). The Company won't let you leave unless you manually shut down five cooling valves to cause the facility's reactor to overheat (and, presumably, wipe out the Xenomorph Hive). You run around and turn the valves, then make your way to a dropship to escape the planet.
- Orbital: The dropship brings you to the USS Odobenus, a space station in geosynchronous orbit above the planet. Somehow, Xenomorphs have gotten loose here too. To make matters worse, several Predators have taken an interest in the station as well. They destroy the docking umbilicus mooring the dropship to the station and then forcibly board. You kill or dodge them and the many Xenomorphs in your path, making your way through crew quarters and a hydroponic lab. Along the way, you must also contend with an experimental security system consisting of "Xenoborgs", Xenomorphs that have been converted into slow-moving but nearly indestructible cyborgs equipped with powerful laser weaponry. You reach an escape pod which takes you to the USS Tyrargo.
- Tyrargo: The Tyrargo is a Conestoga-class troop transport ship. Not surprisingly, it too has become infested with Xenomrophs. You make your way through the very dimly-lit ship, passing familiar banks of cryotubes, hangars, and a mess hall (complete with a combat knife embedded in the table — a reference to Bishop's knife trick in Aliens). After you successfully kill an intruding Predator, the Company betrays you, informing you that you've been "most useful" and leaving you to die. However, after you kill a Predalien, your commanding officer opens a door for you, allowing you to escape. You encounter Praetorians, the Queen's royal guard caste, before taking a service elevator down to the bowels of the ship, reaching the dropship hangar.
- Hangar: The dropship hangar is a large, open space, resembling a larger and better-lit version of the hangars you've seen in the previous level. Whatever weapons you had before are gone, leaving you with only a Pulse Rifle. Unfortunately, you face off against the Xenomorph Queen in this room, and your rifle isn't going to do you a lot of good on its own. You must take advantage of the room itself to kill the Queen, crawling under floor grating (like Newt in Aliens) and ultimately blasting the Queen out through a loading airlock (again, like in Aliens). As the Queen is sucked into space, you retreat into a sealed cubbyhole and watch.
In the ending cutscene, the Marine watches as the Queen is sucked out of the ship... but fails to notice the Xenomorph slime that is dripping behind him...
The Predator campaign is not as coherent as the other species' missions, and takes the player through levels on three separate planets with seemingly no overreaching plot. In the opening cutscene, an unwary Marine fails to notice the Predator's laser sight moving up his back, and is shot from behind with a bolt of plasma.
- Waterfall: The game begins with you stalking Marines outside a military facility with the designation "Area 52" (a reference to Area 51). A Predator ship has been recovered and its occupant captured; your goal is to retrieve them. To this end, you stalk through several security checkpoints outside the base, finally reaching the entrance just past a waterfall.
- Area 52: In the second level, you are inside Area 52 and must fight your way deeper inside. Along the way, you need to retrieve a keycard. At the end of the level, you find your ship.
- Vaults: You retrieve two new weapons from your ship — your Smart-Disc and a Plasma Pistol. You must destroy a series of computer banks to proceed further — but by destroying the computers banks, you accidentally release the Xenomorphs being held in the facility. The human occupants are quickly overrun and, as you progress, you find the labs where Xenomorphs were being held, studied, and dissected. You also find evidence that your comrade was taken here. In the deepest part of the lab, you find that the humans have experimentally impregnated your fellow Predator with an Xenomorph — creating a Predalien. Upon releasing and killing the Predalien, you unintentionally trigger the facility's self-destruct system, giving you only a minute to reach your ship and escape.
- Fury 161: You travel to the Fiorina "Fury" 161 Class C Work Correctional Unit, featured in Alien3. For unspecified reasons, there's an Xenomorph infestation on the planet and the Marines are trying to clean it up. You pass through the lead-smelting facility and through some familiar scenes from the movie, including the morgue, the EEV crash-site, and the main hall. Finally, you reach the outside, and your ship arrives, allowing you to escape.
- Caverns: Your ship takes you to a Marine-controlled Xenomorph habitat. You fight your way through the human defenses, including Xenoborgs and sentry guns, until you reach the Xenomorph Hive. After you fight a pair of Praetorians deep in the hive, a rock floor collapses beneath you.
- Battle: The last level is a single room — the Queen's chamber. You have disabled your powered weapons "to preserve your honor", leaving you with only your Wrist Blades and your Spear Gun. Unlike the Marine's Pulse Rifle, your Spear Gun is sufficient for this task, though you will expend most of your ammunition in the process.
In the ending cutscene, the Predator notices a lone Facehugger sneaking up on it, blasts it with its Plasma Caster, and celebrates with a triumphant roar. However, the next hunting season shall open soon...
The game is a first-person shooter (FPS), but differs from most other FPS in that the player can choose the perspective to play from: Alien, Predator or Human (Colonial Marine). These different perspectives afford distinct capabilities and weapons.
In the most conventional case, playing as a human is the most similar to other FPS video games, and the player is able to access a wide array of weaponry (mostly that from the films). Somewhat unusually for an FPS, the weapons the player uses are subject to stoppages, often leaving them unable to fire at a critical moment; no action is required of the player to clear these jams, other than simply releasing the trigger and firing again. As well as powerful weaponry, Marines wear armour for protection and have an image intensifier and flares to improve visibility in dark environments.
As a Predator, the player may make use of Predator weapons such as the Plasma Caster, Smart-Disc, Wrist Blades and the Spear Gun capable of tearing off body parts and embedding them in walls. Predators are also considerably more athletic than humans, are the most durable creature in the game by far (even surpassing the armor capacity of armored humans in terms of withstanding damage), can make use of a cloaking device to stalk prey, and have a range of different vision modes to aid them in hunting the other species; in addition, they are capable of falling from far greater heights than humans without fear of injury or death. In the game, default Predator vision is similar to that of humans, but an infrared vision mode is available for tracking humans (similar to that in the Predator films), while a vision mode sensitive to electrical systems allows Predators to track Aliens (and android). A zoom function allows the predator to spot and attack prey at extreme ranges.
Playing as an Alien is the most significantly different perspective. Players are able to range freely over any surface regardless of its inclination. This allows wall-walking and completely novel means of attack. However, weaponry is restricted to claws, tail and jaws (for the infamous head-bite), though these themselves reward the player with a fairly unusual experience in FPS combat. By default, Aliens visually perceive the environment in a similar manner to humans, albeit distorted by a fisheye lens to increase field of view; it is possible this view style was influenced by Alien3, which includes footage "seen" from the Xenomorph's point of view filmed using a fisheye lens. Players can also switch to a "sonic resonance" or echolocation mode to increase visibility in dark environments (as explained in Aliens versus Predator 2). This is augmented by an ability to detect pheromones and to discern human or Predator prey. The Aliens in this game can drop from any height without fear of injury or falling, and are the fastest of the three character species that the player can use.
In the single player mode, the game presents a conventional series of levels to progress through. However, because of the differing abilities of the three species, the levels themselves are not always conventional in structure - Alien levels, for instance, often involve climbing through convoluted buildings. The levels are loosely structured, with progression sometimes a little arbitrary (e.g. Predator players find themselves, for a single level only, on the prison planet Fiorina 161 from the film Alien3).
Aliens versus Predator Gold EditionEdit
Aliens versus Predator Gold Edition was released in 2000, approximately one year after the original game. This version adds two new weapons for the Marines (the Pistol and the Skeeter Launcher), the ability to save progress in singleplayer (although players have limited saves depending on the level difficulty) and numerous new multiplayer levels. The in-game video messages (seen on video screens throughout the singleplayer campaigns) were also replaced with newly filmed versions, featuring members of Rebellion's staff instead of the hired actors originally used. Additionally, the Gold Edition included Aliens versus Predator: Prima's Official Strategy Guide.
Aliens versus Predator Classic 2000Edit
In 2010, the game was re-released again under the title Aliens versus Predator Classic 2000 and was made available for purchase via the Steam digital distribution service and the OnLive cloud computing platform. This version of the game was updated to run on modern computers, and included support for the Xbox 360 controller. The bonus levels are also unlocked automatically after completing the final campaign mission for each respective character; in previous releases of the game, the extra missions had to be unlocked individually by completing certain goals in specific campaign levels.
Initially supporting only singleplayer gameplay, multiplayer functionality was added at a later date. Classic 2000 includes all the extra levels and content added in the Gold Edition. A patch released via Steam on 19 January 2010 added proper widescreen support, optional unlimited saves, a locked frame rate, mouse improvements and other updates.
The game was well received by both critics and fans of the franchise, because of its gameplay and dark, yet terrifying atmosphere.
- The game was originally an attempt to make an Aliens-themed total conversion using the Quake game engine. 20th Century Fox however owned the rights, and sold them to Sierra Entertainment to make this game.
- The game was originally going to be released on the PlayStation. The console version was ultimately scrapped because the game's engine was incompatible with the PlayStation.