"Aliens" (often referred to as "X-Rays" by the soldiers) is the Human term used to collectively designate the extraterrestrial enemy force that invades Earth in 2015 under the direction of the Uber Ethereal.
They are the main enemies in XCOM: Enemy Unknown.
- Sectoid - light infantry
- Sectoid Commander - psionic
- Thin Man - infiltrator and light infantry
- Outsider - ship guardian and communication expert
- Floater - aerial light cavalry
- Heavy Floater - aerial heavy cavalry
- Cyberdisc - small hovering vehicle/cybernetic organism
- Drone - support and repair robot
- Muton - heavy infantry
- Chryssalid - terror troops
- Sectopod - heavy assault robot
- Ethereal - psionic leader
- Uber Ethereal - supreme leader
This expansion adds two new aliens types:
The aliens' technology initially outstrips anything available on Earth, including XCOM's in-house development; however, the technology gap is bridged quickly as XCOM's operations yield captured artifacts of increasing sophistication.
The aliens rely on several variants of plasma weaponry ranging from the wrist-mounted Sectoid pistols to the Elite Muton's massive plasma cannons. These variations boil down to the same four basic weapons of increasing power and size:
However, the aliens lack specialist weaponry for either long-range marksmanship or close-range assault, although they have the ability to produce it, as proven by XCOM's rapid development of the Plasma Sniper Rifle and Alloy Cannon designs.
All alien small arms are set to self-destruct after their user's death, although they may leave behind Weapon Fragments which can provide basic insight into the technology.
Berserkers possess wrist-mounted blades for extra damage, although the creatures themselves are dangerous enough.
Chryssalids are living weapons themselves, using their targets to implant their eggs, or ripping them to shreds, all while causing poisoning.
Ground Vehicles and RobotsEdit
The aliens have never been observed using manned ground vehicles. The Cyberdisc is questionably a living creature encased in a thickly-armored transforming shell, equipped with an anti-grav unit and armed with a deadly cannon. Ironically, they also lob standard-issue grenades via centrifugal force.
A simpler yet tougher and more powerful (and psionically controlled) vehicle is the Sectopod, which has a powerful primary weapon and a back-mounted defensive plasma gun.
Another example of the alien technology is the Drone, which can repair larger machinery and is not fundamentally different from Human robotics.
This area remains poorly investigated. However, it is known that some alien devices are designed to be interfaced with by psionics such as Sectoid Commanders or Ethereals.
Aircraft and SpacecraftEdit
The aliens' access to superior hull materials and advanced subsystems such as Elerium-based Power Sources and sophisticated Flight Computers gives them a colossal advantage in aerial power. XCOM Raven interceptors cannot maintain prolonged contact, even without considering the UFO's armaments.
All identified UFO types are larger than XCOM interceptors.
Known UFO TypesEdit
To carry this out, the aliens begin space-borne intrusions on Earth rather than an all-out apocalyptic assault, initially aiming to abduct random civilians to carry out basic experiments. After the XCOM response becomes tangible, the force begins conducting overt "Terror Missions" in populated areas as well as relying on various other means of raising worldwide panic that seems to aim to undermine support to XCOM. However, the Ethereals kept leaving clues that finally brought the most able, most psionically-gifted human onto their capital ship.
With the exception of ship commanders, new enemy units begin to be deployed by the alien forces according to a fixed schedule (see table, below). Species that are introduced in the early and mid-game are generally most predominant during the first one to three months that they appear. Early-game species such as Floaters drop to a very low chance of deployment (circa 2.5%) by late-game, but are never removed from the pool of available aliens. Outsiders are an exception, as they no longer appear following the Alien Base Assault mission.
Operation Progeny and Slingshot DLC missions do not adhere to the schedule and may include aliens before they are regularly deployed (e.g. Mutons can appear in Slingshot missions before May). Similarly, Ethereals may be encountered during the XCOM Base Defense mission in Enemy Within. These occurrences are unique, and do not prematurely commence the appearance of these aliens in other missions.
Within the first seven months all of the non-commander alien species are deployed during regular gameplay. The appearance of new aliens is delayed if the "Marathon" Second Wave option is enabled, indicated by a month in brackets in the table below.
Stats based on Normal difficulty:
|Cyberdisc||16||10||70||0||18||-||Plasma Cannon, Alien Grenade|
|Floater||04||0||50||0||12||010||Light Plasma Rifle|
|Heavy Floater||12||10||70||0||12||025||Plasma Rifle, Alien Grenade|
|Mechtoid EW||20||10||70||0||14||-||Plasma Mini-Cannons|
|Muton||08||0||70||0||12||010||Light Plasma Rifle/Plasma Rifle, Alien Grenade|
|Muton Elite||14||20||80||0||12||020||Heavy Plasma, Alien Grenade|
|Outsider||03||0||70||0||12||020||Light Plasma Rifle|
|Sectoid Commander||10||20||85||0||12||090||Plasma Pistol|
|Seeker EW||05||10||65||0||14||-||Plasma Pistol|
|Thin Man||03||0||65||0||15||015||Light Plasma Rifle|
|Uber Ethereal||25||40||100||0||12||150||Psionic Lotus|
Aliens are subject to a variety of bonuses and penalties that modify their stats during combat.
|XCOM: Enemy Unknown Enemies|
|Aliens|| Berserker • Chryssalid • Cyberdisc • Drone • Ethereal (Uber) • Floater (Heavy) • Mechtoid |
Muton (Elite) • Outsider • Sectoid (Commander) • Sectopod • Seeker • Thin Man • Zombie
|EXALT||EXALT Heavy (Elite) • EXALT Medic (Elite) • EXALT Operative (Elite) • EXALT Sniper (Elite)|