Harvesters

"Peace? No peace."

- Captured Attacker pilot

The Aliens are a race of nameless, highly-intelligent and technologically-advanced beings. They serve as the primary antagonists of 1996 sci-fi action movie Independence Day and its 2016 sequel, Independence Day: Resurgence.

Early history
The first recorded interaction between humanity and the aliens was in 1947, when an Attacker crashed on the Foster Ranch outside of Roswell, New Mexico. In the crash, two aliens were killed, while a third was seriously injured. The crashed ship, the two bodies and the injured alien were brought to the new Air Force installation outside of Rachel, Nevada called Homey Airport, (better known as "Area 51"). The survivor died within a matter of weeks. Over the next forty-nine years, scientists at Area 51 studied the Attacker, attempted to repair it and studied the physiology of the three alien corpses. However, none of the technology of the Attacker could be accessed, as there was no Mothership nearby.

Vietnam War veteran Russell Casse claimed to have been abducted by the aliens in 1986, with the purpose of conducting horrific experiments upon him. However, the veracity of these claims are debatable and as such, Casse was largely dismissed for suffering Post-Traumatic Stress Disorder (PTSD).

First invasion
On July 2, 1996, a Mothership arrives at the Moon and begins to transmit command signals into Earth's satellite system. During this time, a number of satellites crash into the Mothership, which significantly disrupts terrestrial communications. After establishing a permanent position, the Mothership deploys three dozen city-sized Destroyers to position themselves over major cities. The signal progressively becomes weaker after every new transmission, with the end of the signal indicating when each Destroyer should fire upon cities.

On July 3, 1996, humanity is devastated, as the largest cities are now in ruins and hundreds of millions of people are dead. The Destroyers move on to other major cities, with the intention being to destroy every last one within a matter of days. There are a number of attempts by humans to defend themselves against the Destroyers, but each of these ends in utter failure, while the alien casualties are minimal, with only one reported crashed Attacker.

On July, 4, 1996, the tide of war takes an abrupt turn. In the early Nevada morning, the captured Attacker from 1947 is deployed from Area 51 by the humans, with Captain Steven Hiller piloting and computer scientist David Levinson as a passenger. The Mothership summons the Attacker and docks it in the center of the ship. Levinson connects to the aliens' internal network and uploads a computer virus that disrupts the Mothership's systems and causes the shields to go down for fifteen minutes. With this slim window of opportunity, the United States Air Force manages to destroy a Destroyer when Casse goes kamikaze into the primary weapon. This strategy is shared with other nations and the Destroyers everywhere are destroyed. With this turn of events, the Mothership issues a distress signal, calling for other civilizations to come to their aid. Soon after, Hiller and Levinson shoot a nuclear missile into the transport hub of the Mothership and escape. The ship explodes, thus ending the first invasion.

Second invasion
Twenty years since the first invasion, a second invasion force is en route to Earth, as the distress signal was received. Since then, humanity has worked industriously to prepare for another global threat; the nations have unified to create a defense grid around the planet and Moon that incorporates the alien technology from the debris of the first invasion. While the alien materials cannot be reproduced by humans, they can be cannibalized for utilization.

Culture and personality
As a whole, the aliens operate as nomadic swarms that strategically strips planets of their resources. Based from Motherships, the individual alien civilizations travel to their selected targets, then deploy their Destroyers to incapacitate any indigenous populations that could pose a threat. Once the native species are incapacitated, Troop Transport ships are deployed for the aliens to directly invade and begin harvesting the resources.

While the Motherships act as individual civilizations for the aliens, the species maintain a connection with one another. Should a mission put a Mothership in danger, a distress beacon will be activated, prompting the arrival of reinforcements.

The aliens are shown to be completely merciless and single-minded in their conquests. They destroy any indigenous lifeforms that approach them and refuse requests for parlay. Depending upon the mission, the aliens may opt to utilize the indigenous species' tools, such as artificial satellites, as means for accelerating their invasions.

Biology
The aliens are noted for sharing a number of similar characteristics as humans, such as a comparable tolerance for climates and being carbon-based. They average at approximately 5' in height and are about as durable as a human being. While bipedal and generally humanoid, the aliens have extra inverted joints that split the tibia and radius & ulna. Their heads are generally slender, with a pointed chin and a cranium that expends far back into a triangular dome shape. Their eyes are glassy, milky and ovular, with their eyelids being sub-dermal.

The greatest difference between humans and aliens are vocal cords, which the latter lacks; they communicate via telepathy. This extra-sensory feature can be utilized as a horrendous weapon in close quarters, as the aliens can inflict physiological trauma by inducing vivid images and by stimulating pain receptors, effectively discombobulating subjects.

Technology
The aliens are an extremely advanced species in both terms of technology and sophistication. However, they are noted to have reached a plateau in which they have made no major advancements in at least decades, as their success rate has not necessitated them. As linear travel is inefficient, the aliens instead utilize worm holes to significantly decrease the duration of their journeys. The aliens maintain gargantuan vehicles, including Motherships, Destroyers, Attackers and Troop Transports.

The Mothership is a megastructure and central hub for each civilization. It is noted for being 150 to 2,900 kilometers in diameter and constituting more mass than all the smaller vehicles combined. The Mothership provides impenetrable shields to every smaller vehicle via signals. All ships that enter the Mothership's range are put on automatic pilot and brought to dock in the central transport storage facility at the center of the ship. Beneath the storage facility is a staging area, where Troop Transports and infantry are assembled. During an invasion, the Mothership will generally remain at a distant orbit and not engage directly with the target, but will provide shielding for the smaller vessels.

The Destroyer is a 15 mile-wide craft that serves as the primary offensive weapon during an invasion. The ship is dome-shaped, with a command tower protruding from one end, which provides direction. The Destroyer is noted for being slow-moving, but devastatingly effective against populated areas. In the center of the underside of the Destroyer is a large cone-shaped weapon that, after charging, delivers an energy blast has the approximate effect of an atomic blast. There are a number of ports across the surface of the Destroyer that may both deploy Attackers or deliver small, concentrated energy blasts capable of destroying human military aircraft.

The Attacker is a small fighter-class vehicle with the approximate capabilities of a McDonnell Douglas F/A-18 Hornet in a terrestrial environment. The interior is designed to be commanded by two to three aliens. The Attacker is armed with two small energy cannons that serve as viable weapons against small targets. While generally short-ranged, the Attacker can adeptly fly in space, as any other alien craft.

The Troop Transport is a medium-sized craft that only two humans have seen, as no ships of its kind had the opportunity to leave the Mothership during the first failed invasion of Earth. The ship is comprised of an elongated dome with a command structure hanging beneath, in a similar vein as a human zeppelin. While landed the Troop Transport rests at ground level, where ramps lead up to the underside, where scores of aliens may load single-file into it.

While naturally frail, the aliens enhance themselves by wearing large bio-mechanical suits that significantly enhance their strength and make them extremely dangerous in a physical confrontation. These suits are equipped with large arms and legs, as well as a series of slippery tentacles that are not only effective in combat, but also allow the aliens to take over the minds' of their victims and speak for them.

Trivia

 * The aliens were voiced by Frank Welker.