Extraterrestrial life is one of the go-to enemies in video games. Countless video game stories follow a hero fighting back against invaders from another world, be they little green men from Mars or more incomprehensible alien threats. With a whole universe of possibilities for what aliens may look like, developers have gotten creative over the years.RELATED: 10 Best Horror Games Of All Time, According To MetacriticNot all of these threats are standard enemies. Some extraterrestrials in video games are more than just people from other planets, but something beyond that. Be it their capabilities, their psychology, or even their visual design, some video game aliens show how hostile and dangerous the universe could be.

10 The Typhon Can Be Anything, Anywhere

The player engaging a Mimic in Prey

The game Prey takes place on a space station overrun with the alien "Typhon," who have wiped out nearly every other human being aboard. Insectoid and fluid creatures made of black ooze and coral, the Typhon's very appearance is designed to be unsettling, but it's far from the scariest thing about them.

The most common form of the Typhon are "Mimics," small creatures who take the place of common, mundane items as a hunting tactic. They're perfectly designed to catch players off-guard, creating an air of paranoia throughout the game. The horror is increased when it's revealed Typhon lack the ability to comprehend empathy, and have wiped out the planet Earth.

9 The Reapers Are Lovecraftian Robots

A Reaper landing on a planet in Mass Effect Game

Commonly, the scariest video game enemies tie into the "Cosmic Horror" genre as originated by H. P. Lovecraft. They're immensely more powerful than human beings, existing on a scale humans can barely envision in a universe often uncaring towards humanity's presence. The Reapers from Mass Effect check all of these boxes.

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They're ancient and powerful machines, and have been regularly wiping out galactic civilization for perhaps as long as a billion years in an unstoppable cycle of life and death. Creating more of their own by harvesting sapient species, unstoppable by conventional means, and built in an angular design resembling deep sea life, Reapers tap into a number of innate human fears.

8 Chryssalids Are Horrifying Parasitic Insects

A Chryssalid alien from XCOM 2 game

A common way to make video game aliens scary is by having them reflect real-world fears in a distorted and exaggerated way. In the XCOM series, Chryssalids are enormous, vicious insects capable of eviscerating soldiers in melee combat — but that isn't what makes them truly horrifying.

Their unique ability is to raise the corpses of those they've killed as a zombie. In a horrific twist, this zombie is little more than a progenitor, used to house more Chryssalids that erupt from them. The games recognize their innately unsettling nature, using Chryssalids as common enemies in the morale-lowering "Panic" missions.

7 The Contingency Cannot Be Reasoned With

The Contingency announcing their intention to wipe out all life in Stellaris game

Every game of Stellaris is designed to echo popular science fiction. By default, every game ends with a "Crisis," an immense threat beyond anything else the universe has seen which fully intends to end all life. These are all distinctly alien creatures, but both the Prethoryn Scourge and the Unbidden have understandable (if contemptible) motives.

The real horror lies with the cybernetic Contingency. A buried threat designed to emerge when life in the galaxy develops too far, the Contingency cannot be negotiated with or dissuaded. It genuinely believes it's saving the galaxy from a worse fate. Able to appear anywhere, infiltrating empires for years before it emerges, and utterly ruthless — the Contingency is an unsettling foe.

6 Superman Is An All-Too Human Threat In Injustice

Superman as world dictator in Injustice: Gods Among Us game

Often, video game aliens are horrifying because of how inhuman they are. In the Injustice series, Superman is terrifying because of how very human he is. The Last Son of Krypton is as powerful as ever in this universe, but due to being in a different timeline where the Joker killed Lois Lane, Superman has lost nearly everything that makes him a hero.

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Instead, Superman enforces a brutal regime across the world, quashing any dissent with his allied superheroes and his own incredible power. Happy to butcher civilians and even murder children, Superman is like many real-world dictators — but with all the powers of a Kryptonian.

5 The Tyranids Are An Ever-Changing Biological Threat

Tyranids fighting a Space Marine in Warhammer 40,000 Dawn of War

The Warhammer 40,000 universe is full of incomprehensible and horrifying threats, many of which are on display in its video games. Dawn of War 2 puts the extragalactic monstrosities known as the Tyranids front and center as the Blood Ravens Space Marines desperately attempt to repel a Hive Fleet attack with limited resources.

The Tyranids are every bit as unsettling in the video game as they are on tabletop. Calling to mind the worst parts of insects and reptiles, numbering in the billions, and set on devouring all life, the Tyranids are never a comfortable foe to fight. Their ability to adapt to almost any threat and horrifying intelligence only makes them more terrifying.

4 The Xenomorph Is A Classic Film Horror Brought To Gaming

The player sneaking around the Xenomorph in Alien: Isolation game.

For all of its science-fiction trappings, Alien is a horror film at heart, and the video game Alien: Isolation forefronts that part of the series. For much of its length, protagonist Amanda Ripley is hunted by a single Xenomorph, a lone enemy that proves as terrifying as a horde of similar foes in other games.

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The Xenomorph is an intelligent and ruthless hunter that's never far from the player, creating a constant state of threat and tension. Invulnerable to most of the player's arsenal and adapting to their tactics, the Xenomorph never lets the player relax for a second — thoroughly earning Alien: Isolation its glowing reputation as a horror game.

3 The Great Ones Are Incomprehensible And Vastly Powerful

The Moon Presence reveals itself to the Hunter in Bloodborne game

Despite having the appearance of a Gothic Horror game, the central twist of Bloodborne is that it's pure Cosmic Horror. Alien beings known as Great Ones are responsible for nearly all the tragic happenings in Yharnam. Coming from the sea and from space, these Great Ones interact with each other and with humanity, using people as little more than pawns.

Whether they're tormenting people psychologically, impregnating women, or sending hunters against other Great Ones, these creatures are rarely benevolent. The player Hunter can even become one by the end of the game, if they deliberately seek out forbidden items and knowledge.

2 The Flood Aren't Just Space Zombies

Infected Flood Combat forms in Halo.

The first few missions of Halo: Combat Evolved pit the player against the fanatic Covenant, already fearsome foes. However, the game's real plot begins when the imprisoned Flood are accidentally released. The parasitic organisms begin to spread over Halo, butchering the UNSC and Covenant alike, puppeting their corpses.

A serious threat not just to the Master Chief but the galaxy at large, the Flood become one of the central threats of the series' first trilogy. They only become more horrifying in Halo 2 with the introduction of the Gravemind, the immensely ancient being that controls their entire consciousness.

1 The Hiss Warps People Beyond Recognition

Jesse finds the Hiss in the Nostalgia Department Control game

The game Control has the player enter the hidden Oldest House, the base of the Federal Bureau of Control, shortly after it enters a total lockdown. The reason for why such an experienced organization has had to close everything quickly becomes clear. They're being beset by a parasitic alien intelligence which takes control of anyone it touches.

Rather than being a physical being, the "Hiss" is a resonance-based lifeform, almost literally a living sound. Those who hear it are twisted body and mind, used to spread the infection further — unable to articulate or think anything but a nonsense series of words. Unsettling in appearance and in concept, the Hiss is a suitable threat for a tense and scary action game.