It’s Halloween season, the right occasion for spooky fun and we thought it’d be a good time to look at the ten scariest alien races in all of Star Trek.
Whether it’s Halloween or some other day, people love to take risks and be scared. Why else would Taco Bell still be so popular? The desire to be scared or fearful of something is a common response to the unknown, so it’s no surprise that we’re tackling that very concept within the realm of Star Trek. Think about it, aliens of all sorts have been woven into the tapestry of the series, and some of them, when broken down, are horrifying. So we’re going to look at ten of the scariest aliens in Star Trek.
10. Vulcans
You might not agree with this, but boil down Vulcans. Get past the characters, the actors, the Starfleet uniforms. Forget their advanced technology and desire to learn. What are Vulcans at their core? They are super strong, emotionless creatures who have a violent mating ritual – if you’re not a willing participant. They may be the good guys, but they are beyond strong when it comes to how they stack up against mankind. It’s no wonder that the Vulcans are ashamed of their often violent and barbaric history.
9. The Xindi
To be specific, we’re talking about the Xindi-Insectoid and Xindi-Arboreal’s. Why these two specific ones? Well, the Insectoid is what he sounds like, a giant freaking bug, and bugs are gross enough when they’re tiny. Now we’re talking about one that’s the size of a person? Ooof, no thank you. While the Arboreal are probably the most docile alien race that Starfleet ever had a conflict with, have you seen their faces? Yikes, just yikes. That’s a hard face for even a mother to love.
8. Ferengi
Like the Arboreals, the Ferengi make this list for their looks. Bulbous heads, sharp fangs, and just the weirdest noses. Seriously, how can an alien race be so ugly and so bad at just about everything? You’d think they’d have other skills besides ripping each other off.

7. Species 8472
They look like a cross between the Animorph’s Hork-Bajir and the classic alien hunter the Predator. So yeah, if he popped up outside of your window, good luck not screaming like a four-year-old on a roller coaster. Beyond that, they’re also super hard to kill. Essentially you’d need a biological weapon to kill these things. Plus they’re from a different part of space. Another universe if you will. That’s just bonkers to think about.
6. The Breen
The Breen are Michael Myers in space. Doubt that statement? They wear a mask you never see them take off. They hardly feel pain, or at the very least show that they’re in it. They don’t communicate conventionally if at all in most cases and they’re fond of the old ultra-violence.
5. Klingons
Klingons history has long been established. While an allegory for the Soviet Union, the Klingons are now more Viking than anything. Focused on glory in war, an afterlife with an eternal battle awaiting them as members of the “Black Fleet” (non-canon). The fact that an angry, over-sized, perpetually hangry person with super strength and a desire for wine that has the consistency of blood isn’t scary to some is what’s horrifying.

4. Remans
Literally designed to look like a vampire, the Remans are the distant cousins of the Vulcans and Romulans. Great, they’re basically the monsters that Romulans have nightmares of. They’re also better warriors than Romulans, which is why Vrax had two Reman bodyguards. As mentioned, they also are terrifying to look at. They’re essentially a scaly version of Nosferatu and that guy was creepy as hell.
3. Borg
They’re space zombies. If they stab you with their little tendrils (a zombie bite), you become one. Once you get stabbed (bit) the process is fast and then you become a mindless drone that only serves one function, the collective, who are driven to acquire the knowledge and technology of every alien species alive (an insatiable hunger). Plus, StarTrek.com even points out the similarities between the Borg and George A. Romero’s Night of the Living Dead.
2. M-113 aka Salt Creature
Maybe the grossest, ugliest and weirdest alien of all time is the M-113 alien, aka the Salt Creature from the Original Series. The creature is the stuff of nightmares, and its weird mouth just sends chills down the spine. Made worse are the suction cups on its fingers, used primarily to hold its prey as it feeds. The grip it possesses and its oblong mouth help make this space vampire into one of the worst aliens to ever run into.
1. Vidiians
The Vidiians are the scariest alien race in all of Star Trek, but why? What makes this race, unlike say the Salt Creature or the Borg, so much more vile and horrifying. Well, why was Wes Craven so popular? While famous for the Nightmare on Elm Street films, Craven rose to fame for his depiction of humanity at its worse.
That’s the Vidiians.
Yes, in the series they’re afflicted with a disease that eats away at their body and organs, but the way they go about staving off death is to butcher alien races and remove their skin and internal organs. They’re Star Trek’s version of organ harvesters, a real issue in today’s world. They’re a mirror that reflects the depth a being could go for more time. Cold and unrelenting, justifying their actions on the basis of the right to live. Taking live in order to prolonge it.
Even worse? They’re just downright insane. In one of the more underrated episodes of Star Trek: Voyager “Faces”, a Vidiian captures B’Elanna Torres and splits her into two; a Klingon and a human. Sure not the scariest thing ever but the Vidiian who captures B’Elanna tries to entice the Klingon version by killing a member of Voyager, cutting off his face and wearing it to entice Klingon-B’Elanna into being with him.
That’s pure horror.

