Harvester (Skyline)

The Skyline Aliens are most commonly seen as black cephalopod-like creatures with the ability to transfix and utilize the brains of different species to power themselves. However since they are responsible for the creation of Humankind, and the fact the hive mind is bipedal, the Cephalopod-like aliens might either be the aliens servants or creations. So the true aliens are Bipeds similar to humans.

They are responsible for the creation of Humankind who acts like a crop for them to harvest brains to build their army for millions of years.

History
The aliens created the Human race long ago as a mean to harvest human brains to build warriors. After million years have passed, they arrived on Earth and began harvesting humans globally, using their brains to power themselves up and building their army by placing human brains into various bio-mechanical structure. They managed to "harvest" most of the human population and the surviving humans were filled with rage and fury.

After the death of their leader by Trent in his tanker form, decade later, the humans led by the evolved captain Rose manages to master the alien technology and organises the resistance against them in space.

Drones
Drones are squid-octopus like aliens with multiple eyes and glowing lights on their tentacles that they use to bring other species into a trance-like state. Drones have the ability to steal the brain and spinal cords of their prey. Drones have slimy black skin. Drone's are capable of surviving without a Brain but its only for a few minutes; in that minutes a Drone's tentacle or all of the Drone approaches the most close target who have a suitable brain. Drones can be destroyed with high caliber rifle heavy weapon like rocket launcher or explosive due to their hard exo-skeleton, which makes them immune to small arms fire. Furthermore, pulling the brain of their nerve system forcefully will also kill them instantly. The main task of the drone is to harvest brains so the Hive Mind can build Warrior Variants.

Like Tankers, their skin is quite flammable so a flamethrower can kill them by burning them to death.

Hydras
The Hydras are black flying aliens that function as dropships. They patrol regions being attacked and release drones to find prey. They have wings and one big blue eye. They are used as "suicide bombers" when combating enemy aircraft. It is surprising that they do not have any projectile-based weaponry, considering how advanced they are supposed to be. They are also seen hunting down hiding humans.

Tankers


They are incredibly strong, which require large ordinance like rocket launcher or tank shell to destroy but their skin is flammable and this capable of slowing them down. They're mostly 'gathering' the alive prey much as possible and then they take them into a mothership for the use of their brains. Its also logical to say they're the main 'gathering' forces of the Skyline Alien Species. The aliens piloting the tankers see their surroundings while inside using some form of holographic HUD.

Hive Mind Tanker
This is a version of the Tanker mech controlled by the Hive Mind. It is far stronger and more agile than the standard Tanker not to mention having the ability to fire energy blast strong enough to shot down a helicopter as well as retractable claw and hypnotise to abduct humans into the mothership.

Warrior
The Warrior variation is the result of an abducted human brain placing into bio-mechanical alien body and being mind-controlled by the Hive Mind from the Mothership. They serve as foot soldiers to the alien race. Due to fact that they are based on human anatomy, their weakness is their necks in which a shot or a stab to the neck will be fatal to them.

They are extremely strong since they can tear human limbs apart. The Warrior can be free from mind-control of the Hive Mind by a Hybrid or if the brain of a person manages to expose and escape the initial hypnotize.

Hive Mind
Hive Mind is the leader of all the alien forces who control and coordinate all the activities of the aliens on Earth ranging from harvesting and attacking human settlements. The Hive Mind is the alien in their pure form.

Without the Hive Mind, all other alien forms minus the Red Lighted ones will collapse.

Evolved
The alien hypnotizing light can be used to create the evolved. So far Rose is the only evolved. An evolved has accelerated growth rate who can grow from an infant to a three year old in a matter of day as well as into a 30 year old woman in 10 years.

Red lights
Red lights are human-brained aliens who escaped from the Alien Hive Mind control and remember their human past before becoming aliens due to the effect of the serum created from Rose's blood that is disconnecting the mind control connection of the Hive Mind to the Warrior. Contrast to the blue light alien, the red lights emit red eyes and have the free will of a human to fight back the alien.

Humans who initially escaped the hypnotize will have the high chance to turn into Red light alien when their brains being put into the Warrior bodies as was the case with Jarrod after being exposed and escaping from the alien light multiple times.

Abilities and anatomy
Most of these aliens have the ability to hypnotize a host and feed/power up by "brains" unless a host is blind. They have a blackish-purple blood (the purple hints at haemoglobin). The aliens suck prey into their body through holes or mouth-like orifices. Only the Drones have the 'power' to transfix in this way. This is unlikely to be an evolutionary trait, due to its sophistication and seemingly impossible effect. It could only be a technology that they have developed. They are able to regenerate lost tentacles with great speed. The blue light they generate to hypnotize can also enhance the creatures that escape the initial hypnosis. An example was Jarrod (having been saved earlier from the alien's hypnosis) showing increased strength and aggression, with his eyes glowing blue and the skin/veins around his eyes darkening - just the same as what happened when he was first hypnotized. His increased strength was shown first when he lifted and pinned Oliver against the wall as he vowed to protect his family. It was shown again when Jarrod and Elaine were on the roof before been attacked by a drone. When the alien attacked Elaine and tried to take her brain, an injured but strengthened Jarrod knocked the alien off her before physically attacking it by hitting it with a breeze block and then using his fists. Finally, he ripped the drone open before tearing out the human brains it had acquired. Furthermore, it is also shown that creatures escape the initial hypnosis also build up immunity to their hypnotizing light and able to turn into Red Light alien after their brain being put into a Warrior Variant body.

It is shown that prolong expose to the Alien energy or its hypnotizing light will cause pregnant women to produce an Evolved like in the case of Rose who are Jarrod and Elaine's daughter. However, the production of the evolved will be fatal for a woman due to acceleration of growth within the womb causing fatal child birth complication to the woman. The Evolved is extremely dangerous for the Alien as they are immune to alien mind control but also can cut the mind control connection between Hive Mind and Warrior. However, the acceleration of growth of an Evolved after making them to depend on blood transfusion from humans that connect their DNA with the Alien retractable arm-blade to survive. According to Harper when he researches Rose blood, the alien DNA is compatible to human DNA making them able to hypnotize humans with their light, however, evolution of mankind making the hypnotism and mind control of the aliens to be useless against the human infant in the embryo who are exposed to the light and they can reverse the mind control functions of the alien to free others humans.

Technology
The technology of the aliens seems to be a fusion of metals and organic components, suggesting an extremely advanced biomechanically driven species. According to Colin Strause, even the motherships are creatures of some kind with their own DNA. Despite the motherships being considered "living organisms" they do have a fair amount of electronic and mechanical elements such as the fact when the ship goes down in the second movie it's seen electronically sparking and a metallic creaking noise is heard. The main command centre of the ship is nearly fully inorganic with metallic floors and a hyper powerfull holographic supercomputer/security system. This suggests they are a highly cybernetic race. Some of the machines/creatures seem to be able to rebuild themselves even after a nuclear strike, though these might be destroyed if the explosion is in the interior. However, it is revealed that the ship can only rebuilt itself if the HIve Mind Alien is still around to start the rebuilt sequence in super advanced computer at the control center of the ship so if the Hive Mind dies, the ship will be permanently destroy.

This is a list of machines: The motherships are made with a metal hull and organic substances on the inside, a tractor beam, and the device that enables the aliens to hypnotize. They look saucer-like, but with spirals and arches sticking out.

Their abduction devices are tractor beams, accompanied by a bright blue light, that can suck Humans into the air, and possibly descend from their ships. The 'alien sorter' is a thin robot with a blue light on the front and a 3-pronged claw, razor blade, and a tube that sucks up the brains into a room that attaches it to the aliens. Retractable blade is weapon used by Warrior variants that are strong enough to punch through all kinds of alien bio-mechanical machines. Blue energy bomb is ball-shaped bomb that can cause a great hypnotism to Humans and a massive explosion that is strong enough to destroy the mothership.

Appearances

 * Skyline (2010)
 * Beyond Skyline (2017)