For decades, humans have been exploring the concept of aliens in pop culture. There have been thousands of films, television shows, games, comics, and books all themed around alien races, invasions, and apocalypses. It's certainly a trope in gaming, as there are countless titles dedicated to assuming the role of one charged with protecting the Earth (or another planet) from an alien invasion.

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There's a lot of attraction in an alien-based title, mainly owing to the fact that they allow a developer to pour in a hearty helping of creativity. When creating an alien race, the developer is bound only by their imagination, which has given way to some terrifying, intimidating alien races being made in the last two decades or so.

1 Helghast (Killzone)

a lineup of all the types of Helghast soldiers from Killzone

In Killzone, the Helghast are a people from the planet Helghan, a world far from Earth. They're inherently violent people, eager to sow war and wreak havoc on their local system. In Killzone, released in 2004 for the PlayStation 2, players watch first-hand as the Helghast invade Vekta, another planet, and begin slaughtering innocent civilians.

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As a collective, the Helghast is driven by maniacal, tyrannical leaders that have warped the minds of what could have been regular, everyday citizens. It's a military-first planet with universal domination in mind, and with a dark, foreboding aesthetic twinned with an apparent bloodlust, the Helghast truly is an intimidating alien race.

2 Typhon (Prey)

A typhon stalks a corridor in Prey

In Prey, released in 2017, things quickly turn sour for the player, as the game opens up and within a matter of minutes, terror is brought crashing down around them. On a space station called Talos I, a hostile alien race called Typhon invades, laying waste to all on board the station - which is orbiting Earth at the time.

Typhon are remarkable, possessing abilities once thought to be mythical: telekinesis and pyrokinesis, teleportation, mind control, and self-regeneration. From the smallest mimics to the hulking, terrifying Nightmare, there are many variants of Typhon that the player must do battle with. Some are so powerful that they cannot be defeated, and the player is left with no choice but to run for their life.

3 Necromorphs (Dead Space)

Isaac Clarke fights necromorphs in Dead Space

Necromorphs are some of the most terrifying creatures to ever grace the world of gaming. They're seen in the Dead Space franchise, which debuted in 2008, and they're essentially reanimated corpses brought back to life (somewhat) by a parasitical pathogen. However, once animated, a Necromorph is extremely powerful, able to kill the player in a matter of seconds.

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There are various types of Necromorph, and while they all have their weaknesses and vulnerabilities, they are, for the most part, formidable enemies. They have a habit of appearing when least expected, leaping out from the shadows and through air vents. As Dead Space is a sci-fi horror franchise, it comes as no surprise that the Necromorphs are some of the most terrifying and intimidating aliens in gaming.

4 Chimera (Resistance)

Chimera aliens screaming in Resistance

Resistance: Fall of Man was a launch title for the PlayStation 3, and served perfectly to highlight the capabilities of what was then the next generation in gaming technology. In Resistance, the player is charged with defending the Earth from the Chimera, a vicious alien species that have invaded the planet and is infecting and mutating all lifeforms.

Like almost every other alien-based title, Resistance featured multiple variants of the Chimera, each one as deadly as the next. When infected with the Chimera pathogen, a human would mutate and join their ranks, and for a while, it seemed as though the human race would win the war against these terrifying creatures. While the last Resistance title launched in 2011, the Chimera remains one of the most chilling examples of an alien race in gaming.

5 The Zin (Saints Row)

Zinyak and his followers in Saints Row IV

From the moment Saints Row 4 begins, players find themselves fighting The Zin, a dastardly race of aliens hellbent on destroying the Earth. Bizarrely, going against action movie and video game tropes, the Earth is successfully blown up by The Zin within a matter of minutes. It's a shocking moment, as, in almost every alien film, television show, or game, the world is ultimately saved from its imminent destruction.

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The Zin are led by Zinyak, a hulking, towering alien commander with impressive combat skills, high-tech weaponry, and an army of Zin at his disposal. While Saints Row 4 maintains a comical vibe throughout, as per the franchise's style, there's no discrediting The Zin as a capable and terrifying alien race. They accomplished what countless other aliens have failed to do: they destroyed the Earth.

6 Xen (Half-Life)

Vortigaunt alien in Half-Life

Xen is a border world in Half-Life, located in a separation between the multiverse, and it contains an array of freakish aliens known, quite simply, as 'Xen'. In Half-Life's multiverse, the Xen are led by Nihilanth, a bizarre-looking alien that is attempting to find a safe haven for his race, and ultimately, much of the race finds itself on Earth following a scientific catastrophe.

Brought to Earth by the 'Black Mesa Incident', the Xen aliens are diverse, ranging from the non-hostile (but still creepy) Vortigaunt to the Headcrab aliens that reanimate corpses and assume control of them. As Half-Life was released way back in 1998, it's often considered the forefather of most modern alien survival games, and it certainly gave way to the creation of one of the most intimidating alien races ever.

7 Covenant (Halo)

Covenant aliens in Halo

Technically, the Covenant isn't so much a single alien race as it is a collection of races. There are several alien species that make up the Covenant, such as the Kig-Yar, the Unggoy, and the Sangheili, and they're all united with one chief goal: wipe out humanity by any means possible.

As one of the most organized examples of an alien congregation, the Covenant was structured, and political, and boasted a massive military force. That alone is enough to make it an intimidating prospect, but the alien races that make up the Covenant are quite good at what they do, even going so far as to give the legendary Master Chief a firm run for his money.

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