Alien Entities (Arma 3: Contact)

The Alien Entities are the machine constructs of an unknown alien race that appeared during joint NATO-Livonian training exercises in the fictional country of Livonia.

In the non-canon DLC Arma 3: Contact, they visit the Earth over the course of one night, seemingly to dig up and remove incredibly energy-dense nodes from a vast underground network of unknown origin. Their arrival was preceded days earlier by an unusually intense neutrino storm, and their arrival itself caused a localized EMP-like event that created confusion among the NATO forces.

Background
The Extraterrestrials represent the scientific and defence forces of an unknown species, stated to originate somewhere in the Sagittarius constellation.

Their presence on Earth consists solely of airborne drones that serve a variety of purposes, including scientific measurements and defence. Their weaponry is gravity-based, utilising matter taken from the surrounding environment which is then condensed and superheated into projectile form.

Although their drones communicate on the broad electromagnetic spectrum, the Extraterrestrials exhibit the ability to broadcast images and sensations directly into the minds of organic beings.

Appearance
It is speculated during the campaign that the robotic entities are constructed in the image of their creators. One scientist believes that Alien Entities evolved in a dark, watery world with strong currents in orbit around a red dying star. This environment is reflected in the fin-shaped drones they use. Accordingly, their speculated natural means of communication is via the electromagnetic spectrum, rather than sound or light, which would have limited utility in their natural environment.

Equipment
Although the Extraterrestrials are not an "army" in the conventional sense, their drones utilise various modules and tools as a form of weaponry.

The smaller Alien Entities demonstrate the ability to manipulate local gravity, and use this to hold tools and resources in various orbits around their hull. These tools include the Scan Module and the Gravity Tool Module; a research tool and weapon/manipulator (respectively).

The Alien Entities also collect and superheat matter from their environment to use as ammunition - up to six of these "matter balls" are held in orbits around the central hull and are fed into the Gravity Module when attacking.

In addition, all drones are largely impervious (though not completely invulnerable) to human weapons. In combat situations, the drones have demonstrated several means of defence, ranging from less-than-lethal (LTL) gravity bursts to ranged, semi-homing missile-like objects with area of effect blast and lastly, a "gravity cannon" that is effective against single targets.

The drones have two means of active defence. The first is a "light burst" countermeasure that overwhelms and disorients targets with noise and light, akin to a prolonged stun effect found in human-made flashbang grenades. The second is a pulsing "force field" that can catch and redirect projectiles as well as temporarily prevent movement.

Methods of travel
Scientific consensus on how exactly the Extraterrestrials were able to arrive on Earth is divided. However, it is widely agreed upon that a mass cluster of neutrinos - released from the root network at the SIŁA factory into space, was one of the primary causes (if not the main factor).

One theory posits that The Visitors began their journey hundreds of thousands of years ago in pursuit of the roots, and timed their arrival in the system for just after the network began broadcasting.

Alternately, a second theory states that because neutrinos may travel faster than the speed of light, the neutrino messages arrived at the alien homeworld before they were sent - travelling backward in time from the moment of their release. Accordingly, the aliens were acting on acausal information while still somehow obeying the speed of light.