25 of the spookiest underwater creatures you’ll ever see

The ocean is dark and full of terrors.

The way these creepy underwater creatures evolved to adapt to immense depths and unfathomable conditions is wild.

1. Sarcastic Fringehead
While the name “sarcastic fringehead” might not strike fear into your heart, it should. It’s a known fact that abundantly colored creatures tend to be deadly, and this horrifying fish is no exception. All you need to do is take a look at its terrifying face.

While this fish actually poses little harm to humans, its horrifying appearance would certainly be enough to make you jump out of your skin. Also, let’s not forget that panicking in the water isn’t necessarily the safest of experiences. You can find this colorful beast off the coast of the Pacific Ocean between northern California and Mexico. You’ve been warned.

2. Lamprey
The lamprey is one of those creatures that you would be better off never seeing in your lifetime. It holds similarities to some of our most ancient vertebrate cousins, dating back to sometime around 540 million years old. It is, undoubtedly, one of the grossest and most vile of all oceanic creatures. It’s safe to say that if this thing tried to latch onto someone, they would likely freak out beyond reason.

Other than that, the thing looks like a tube that was filled with teeth so it could tear right through anything and everything. Truly something made of nightmares. You’ll find these beasts in the Atlantic Ocean and in the Great Lakes. Now you know to avoid these places entirely.

3. Giant Squid
The ocean depths can breed some amazing things. The giant squid is one such thing. Growing magnificent sizes due to something called deep-sea gigantism, the giant squid is one of the largest and most formidable predators of the sea. You can tell by these horrific scars.

Not only does it have long tentacles with horrifyingly strong suction cups, but it has a beak that it can use to peck through skin. While this thing mostly resides in the depths where humans won’t find it, simply knowing that it exists in the same water that you might be swimming in is enough to induce fear.

4. Black Dragonfish
If you haven’t realized it by now, the ocean is full of the most reprehensibly disgusting creatures on earth. The black dragonfish is just another one of these. It comes complete with horrible, goblin-like fangs that can rip through flesh, and a taste for blood that sends it out for the kill.

But, strangely, it is only the female black dragonfish that has these ugly qualities. The female looks black, slimy, eel-like, and just all-around gross and terrifying. Like the giant squid, however, you will only find the likes of the black dragonfish deep down in the sea. So you’ll likely never actually come across this horrifying creature.

5. Gulper Eel
Fortunately, many scientists feel inclined to name species with a common term so we can all understand. The gulper eel is one particularly apt example of this. Nothing but a short look at the thing will reveal a great propensity to gulp. In fact, it looks as if its sole purpose was to gulp.

Like the anaconda, the gulper eel takes to its foes by swallowing them whole. All it has to do is open its mouth, say the rosary, and engage. After a quick few seconds, the prey will have slid down the gulper eel’s gullet, never to be seen again.

6. Frilled Shark
Frills are those things that garnish ornate clothing—and you can tell why this shark got that name. A quick glance at that gnarly head and you’ll see the frills. Regardless, this thing most definitely does not remind me of fancy frills and ruffles. It is just as terrifying as it is nonsensical.

Like most sharks, the frilled shark can be extremely dangerous. It is infamous for its numerous rows of sharp and deadly teeth. Many of these creatures have as many as 25 rows of teeth. That is a disturbing number of teeth. Keep this in mind as you meander about the ocean waters.

7. Anglerfish
The anglerfish is one of the most stereotypically terrifying fish species out there. It has a giant, ugly jaw, a bioluminescent bulb, and a predatory disposition that says “leave me alone or I will eat you and your entire family.” You can just tell it has an insatiable thirst for blood.

Thankfully, we are not one of the foods that the anglerfish consider prey. The anglerfish makes its home in the depths of the ocean, luring in fish with its glowing blue light. Once a fish comes close enough, the anglerfish snaps forward and entraps it within its jaws. The result is what we call “dinner.”

8. Giant Isopod
The giant isopod is a species of crustacean that looks otherworldly. As with most crustaceans, it has a hard shell that you would not want to bite into, some antennae that you would not want to bump into, and a bunch of tiny legs that are grosser than gross.

It’s almost as if you summed up all of the worst possible things in the animal kingdom and placed them into one creature. Anyway, the giant isopod is one of the largest of the sea crustaceans, feeding on animals that have died of other causes. In that regard, it’s kind of like a mushroom of the sea, only far more disgusting.

9. Goblin Shark
The goblin shark is a species of shark that I will never want to see. Moreover, it is one of those shark species that has a name so perfectly chosen that we balk at contemplating it. It’s almost as if the concept of goblins came after the discovery of this shark.

Regardless of what came first, the goblin shark is not something to be trifled with. While it’s small, it has an abundance of needle-sized teeth which, if they penetrate your skin, can leave nothing but a bad time. This is not a goblin with which you would like to tango.

10. Vampire Squid
The vampire squid, despite its name, is not all that grotesque a creature. It doesn’t suck blood. It doesn’t squirt ink. All it really does is swim around with weird tentacle things, floating around in the water. So, contrary to most other creatures on this list, you needn’t fear the vampire.

But, again, as with most of the other things on this list, the vampire squid is something you’re really only going to find very deep down in the ocean. It lives so deep in the ocean that you’d have to dive down in a vessel to see it for yourself.

11. The Snaggletooth
The snaggletooth has a disposition for death. Even one glance at the creature can strike so much fear as to render you completely paralyzed. We’d recommend that if you see anything that looks remotely like this creature, that you turn around and run (er, swim) away as fast as you can. Do it quickly.

These things are the stuff of nightmares, and if you like your sleep undisturbed, we recommend that you close your eyes and wish this bad boy away. Otherwise, you’ll be sleeping with the fishes—an ugly statement that originated to describe nightmares about this fish, we’re sure.

12. Black Swallower
One might ask oneself why the sea has evolved so many terrifyingly creepy creatures. And the answer would be simple: The water is no place for those who care about looks. You don’t have fish movie stars, or fish Brad Pitts. In fact, this thing is like the polar opposite of beautiful.

If we did have fish Brad Pitts, this would certainly not be him. Instead, it would be something like a Rob Schneider: popular at one point yet wildly inappropriate at others. Anyway, you might want to avoid this fish if you plan on doing any deep sea diving. The thing will likely scare you into some sort of paralysis.

13. Grenadier
Grenadiers are just as pervasive as they are terrifying. If you were to find one, the result would likely be that your shudder is one last quake of death. This is especially troublesome given that you can find the horrid beasts almost anywhere on planet Earth. This is another reason we should travel to other planets: They likely don’t have any grenadiers.

Fortunately, the grenadier lives deep down at the bottom of the sea. Here, looks don’t matter, and evolution will slowly guide you away from the pretty and nearer to the grotesque. After enough time, you will be so unbearable that you will never be able to reenter society. Sorry, grenadier fish.

14. Barreleye
The barreleye is one of the weirdest fish in existence. Its head, contra to yours and mine, has evolved a translucence. The reason for this was so that it could see up and around it to watch for incoming predators. But another reason was likely to scare the bejabbers out of us humans.

When one looks at this fish, one can’t help but picture some horribly created B-movie where a monster tricks people into thinking it has candy. Only afterward would those people out that the monster isn’t some normal person working at a candy shop, but instead some terrifying goblin-type thing with a lust for blood.

15. Asian Carp
Asian carp have some strange idiosyncrasies. First off, they’re not necessarily Asian—you can find the fish in North America in places like the Great Lakes. Second, they are considered a horrible pest of a species. But other than that, the fish also offer some terror. This terror comes neatly packaged in the jumping ambitions of the fish.

And what, exactly, is it that these fish do? Well, they leap from the water all at once, spooking anybody who’s nearby. When dozens of fish begin to leap several feet from the water, the result isn’t exactly a cool consciousness. Instead, it’s something reminiscent of a pestilence.

16. Fangtooth Fish
We’re not sure why it seems a prerequisite in fish evolution for all aquatic creatures to be ugly. We should really try and petition natural selection to start evolving some fish dentists to get the job done. I mean, just look at those teeth!

Anyway, the fangtooth fish is one of the gross, scaly creatures with a bunch of sharp teeth that you would rather avoid if you want to live. While the thing doesn’t necessarily hunt humans (you aren’t a deep sea animal, after all), they most definitely would if they could. You can just see the murder in their eyes.

17. Alligator Gar
The alligator gar is one of the most terrifying of the all the terrifying swamp-like creatures. If you had to rank them on a scale from one to awful, they’d scale pretty heavily toward the awful. The creature comes entirely equipped with a body that looks like an alligator, yet comes with a set of fins that lets it swim like a fish. Terrifying.

The alligator gar has some other terrifying characteristics. First off, it can weigh up to a staggering 230 pounds, making it one of the largest freshwater fish species in North America. But the alligator gar also has many interesting traits. It is, for instance, considered a “living fossil” for things like its spiral valve intestine.

18. Snakehead Fish
When a fish has the head of a snake, you know you’re in trouble. And that’s what we have here: a fish that appears to bear the head of a snake. What’s more is that it’s large, scaly, and slimy. But because the species is considered invasive, it is doubly worse.

Another reason the snakehead got its name is because of the unique patterning it has on its body—it looks like a snake! You see the striped pattern that makes it look as if the thing is trying to blend in. It probably is. The fish is so scary that it inspired the 2004 film “Frankenfish.”

19. Northern Stargazer
The northern stargazer is given its name not because it has a penchant for astronomy, but rather because of the placement of its eyes. This sea critter has adapted to a life at the seafloor, where it preys on fish that swim above it. Amazingly, the way in which it adapted was to move its eyes to the top of its head.

If you see this creature at the bottom of the sea, don’t panic: Panic only makes it stronger. It’s like one of those mythical beasts you’ll find feeding on fear in Norwegian folktales. Unlike the sarcastic fringehead, however, this is a beast you will find on the eastern coast of the United States. Again, you’ve been warned.

20. Megamouth Shark
When a species has “megamouth” in its name, you know it should probably be avoided. And this is in fact the case with the megamouth shark. The creature comes surprisingly well-equipped with terror-inducing glares. It’s when it opens its mouth that things get really gross, however. Those who find these things washed ashore often have nightmares about the ugliness.

Fortunately, the species is rare, which makes the likelihood of actually encountering one slim to none. Also, fortunately, the thing really only consumes krill and other small fauna of the sea. It took an evolutionary pathway that fed on small creatures. This wasn’t like other sharks.

21. Megalodon
The megalodon is the most terrifying species ever to have roamed the water—or at least one of the most formidable. The thing could grow to the size of two full-sized school buses. But beyond that, the thing would prey on whales — whales?! Anything that has enough size to prey on whales is not something we would call our friend.

Fortunately for us, the megalodon went extinct tens of millions of years ago. But even if it hadn’t gone extinct, the thing would have preyed on other horrifying oceanic creatures like the great white shark. It’s hard to say whether the thing would be a nuisance or a godsend.

22. Saber-Toothed Viperfish
The saber-toothed tiger was one of those creatures we all raved about as children. It had giant teeth that it would have likely used to break its prey’s neck or puncture its throat. The saber-toothed viperfish is only slightly different. Although that difference doesn’t mean you shouldn’t be afraid.

Rather than use its giant (at least proportionally) teeth to break its prey’s neck, it uses them to puncture the skin and entrap them. These teeth are used to help immobilize the prey, such that it can’t escape. The thing lives in warm tropical waters. I’d keep that in mind if I were you.

23. Sea Slug
The sea slug is not one of the most terrifying oceanic creatures. It is, in fact, one of the more benign. This doesn’t, however, make it unmysterious. One quick glance at the species and you realize that it’s emboldened with its bright colors. And you know nature’s rule about brightly colored creatures: in most cases, you should stay away.

The thing has teeth (hidden within that slug-like body) which it uses to tear apart its prey. So yes, despite its benign appearance, the thing has a penchant for flesh. If you see one of these guys in the water, we recommend that you turn around and swim away immediately. They’ve been known to attack the unsuspecting human…

24. Sea Cucumber
The sea cucumber does not seem like it would be one of those things that kills you upon first sight. Unfortunately, this creature has a defense system that can be lethal. When spooked, the animal releases a potent toxin called “holothurin.”

Once ingested, this chemical can kill. This is in part why the tribes native to California and elsewhere would use it (once isolated from plants with the same chemical) to kill off fish species: All you have to do is put it into the water. If you’re trying to avoid death-by-chemicals, we’d recommend you let these things be. Otherwise, you might get a bit more than you bargained for.

25. Blobfish
The blobfish is more disturbing than it is spooky. When taken from its aqueous environment, the thing looks like a deflated (and not to mention disgusting) blob you would expectorate when sick. Yuck. If it doesn’t remind you of such unpleasantries, you might instead be thinking about its resemblance to a certain character from a certain cartoon show…

Either way, the thing lives at extreme depths of around 1,200 meters. This puts it far beyond the reach — and sight — of local New Zealanders, where the thing lives. The only time you have to fear encounters with this thing is during walks along the beach.

26. Amphipod
The amphipod is one of those strange creatures that glows in the dark. When you see the things, you might be reminded of ghostly spirits. The amphipod is not, however, of some ghostly realm. Instead, it is just a deep sea creature that has adapted to the floors of the Pacific Ocean.

These creatures, however, can evolve beyond the one-inch typical to such tiny crustaceans. These things can grow up to one foot in length. They are, in other words, some of the most formidably strange translucent animals you’ll find in the deep. We won’t in other words, see much of this guy.

27. Coffinfish
The coffinfish is given its name because it likes to inhabit the coffins of the buried dead. Just kidding. The coffinfish is given its name because it looks like something creepy and resurrected. It’s not something you would really like to see while enjoying your vacation in the Bahamas.

Fortunately, you are unlikely to have such an encounter. The forebodingly named fish lives in the deep-sea environment, far sequestered from human sight. If you dive, however, you might find this thing expanding and contracting its size like a pufferfish. And if it is the thing you see, prepare yourself. Its shocking nature might induce panic.

28. Dumbo octopus
When most people think of octopi, they think of those eight-tentacled things that swim with terrifying becks and attack whales. Not all octopi are like this. The dumbo octopus, as seen here, does not seem capable of attacking much of anything. It seems more likely to fly away with its ears than do any harm.

Clearly, the dumbo octopus does not really pose a threat. The only threat that it really offers is that it might induce you to die from cuteness. Maybe you see the thing while diving, get distracted and forget that you’re running low on oxygen. You’re probably safe around these guys, though.

29. Hatchetfish
The hatchet fish is one of the more interesting of deep-sea creatures. Clearly, that’s because of its looks. It’s shiny. It’s ugly. And clearly, it has a ravenous taste for human flesh. If you see this thing, you had better swim away fast. The thing has a penchant to kill.

In reality, the fish doesn’t really pose a threat to humans — nothing that lives in the deep sea does. What this thing does pose a threat to is the fish that swim above it. What it does it uses it tubular eyes to detect movement from above. When it does, it primes itself for attack.

30. Blue-Ringed Octopus
The blue-ringed octopus is, contra to many of the animals that have made their way onto this list, an extremely dangerous creature of the sea. If you encounter this extraordinarily beautiful creature, you will want to avoid it as best as you possibly can. As with many things in nature, it signals this with its beautiful and resplendent coloration.

The blue-ringed octopus has a venom that can kill very quickly. What makes things worse is that the thing has no current antivenom. So if you encounter the organism, you will want to avoid it as best as possible. It does have the potential to kill.

31. Moray Eel
Eels are invariably disgusting creatures. One look at them and we say, “no thanks.” They have teeth. They can shock you. All of these things are bad. You can find these creatures in the South Pacific Ocean, so you should probably avoid that if you want to be safe.

The moray eel resides in the deeper waters, however, making it relatively safe to swim on the surface. Moreover, the thing isn’t really large enough to take on humans as prey. We should consider ourselves exceptionally lucky for this. We, for one, cannot imagine having to battle off these eels like Buttercup battling the shrieking eels in “The Princess Bride.

32. Big red jellyfish
Jellyfish normally aren’t the worst things in the ocean. The animals feared over them are as well-known as great whites to alligators. However, many people don’t know about the Big Red Jellyfish. Named for its formidable size, the meter-wide jellyfish looms the sea looking for victims. Definitely frightening.

Fortunately, the deep-sea jellyfish is not that likely to encounter humans. While it may be ugly, it doesn’t have tentacles that sting. Instead, it has “feeding arms” that reach out and eat its prey. Despite its size, we are not one of these prey species. And for that, we can be thankful.