12 Mythical Sea Creatures No One Believes Existed

In 1995, a ship vanished after sending a single message, mass under hull. What did they see beneath the waves? Today, we're diving into 12 real sea monsters that might still be out there. And stay till the end, because one of these creatures doesn't kill, it just makes you vanish without a trace. The first creature in our video is Lusca, native to the Blue Holes near Andros Island in the Bahamas. Lusca is described as a part shark, part octopus, and is over 75 feet long with powerful tentacles and a huge mouth lined with spiraling teeth. It resides deep below the surface and silently strikes its prey, killing it before it even has a chance to react. Even today, when reports surface of swirling currents pulling boats under without warning or divers disappearing despite calm conditions, some people just shake their head and say that the Lusca took them. According to some scientists, Lusca could be an undiscovered species of giant squid. But whether it's a beast or a myth, one thing is for sure, take the advice of locals and never swim at night lest you become dinner for the Lusca. However, Lusca isn't the only giant in the deep. In Japan, a creature waits that can turn the sea red, literally. Next on our list is Okorokamoi, a fearsome creature that lives in the northern part of Japan. He is often described as a gigantic red octopus or squid and is said to be over 100 feet in length. He is believed to inhabit the waters off the coast of Hokkaido, particularly around Funka Bay. According to the legend, Okorokamoi was a powerful spider named Yaoshikep who devoured the whole village. When the gods saw what he could do, they banished him to the seas, where he became something even worse. Whenever he rises, the ocean turns blood red, the sky dims, and the creature's vast form blocks out the sun. While people believe it to be nothing but folklore, there are many sightings of Okorokamoi. In 2007, divers off Hokkaido captured sonar images of a massive moving mass, only for their equipment to fail soon after. Later on, a rescue team was sent out for the divers, who found their boat empty and untouched, as if they simply stepped off. Biologists suggest that these events could involve rarely-seen giant Pacific octopuses or bioluminescent jellyfish blooms, yet locals believe these are signs of Okorokamoi watching. So, in shrines near the coast, offerings are still made to appease the ancient sea god. Otherwise, Okorokamoi will devour the entire village once again. That's brute strength. But what if the next monster could disguise itself right in your fishing bucket? But while Okorokamoi is dangerous just because of his size and strength, the next creature on our list is dangerous because of its deception. And the worst part is that it feasts on humans. The Syrian crow-in can shrink into the size of a silverfish and wriggle its way into a fisherman's catch. Once he is caught, he waits for the perfect opportunity and hunts down his prey. Legend has it that a fisherman once caught a silvery, unfamiliar fish. He brought it home in a wooden bucket. That night, screams tore through the village. Neighbors found the cottage split open, as if something the size of a house had burst out. No bodies were ever recovered, only streaks of slime and shattered timber. Others claim to have hooked a fish that changed shape mid-air, twisting as it landed on the deck. Even today, sailors still warn each other, if your fish blinks, throw it back. And if you thought shapeshifting fish were disturbing, the next creature doesn't hunt. It devours moons. However, one of these creatures isn't a legend. It's still feeding. Moving on to the Philippines, where during lunar eclipses, the old rituals begin. Drums beat, metal clangs, and fires burn along the beaches. It is not just a tradition. It is a fear that he might rise above and devour the moon. It is an attempt to scare off Bakunawa. Bakunawa has glistening black scales, glowing red eyes, and a mouth wide enough to swallow islands. He is so big that he could bridge the gap between water and the moon. He wasn't always a monster. Ancient myth says Bakunawa fell in love with the moon goddess. But when she rejected him, he lashed out in fury, biting her and tearing her light from the sky. In 1951, villagers near Surigao del Norte reported seeing the ocean surge backward during an eclipse. The water turned black. Fishermen refused to sail for days. One child even disappeared from the village that night, her small footprints leading into the sea. But no tide ever returned her. So even today, during a lunar eclipse, many begin their old rituals, hoping that it would be enough to keep away the Bakunawa. The next sea creature on our list has a serpentine body with dark, rubbery skin, and glowing red eyes. It is said to swim silently beneath the surface, watching and waiting for the perfect moment to attack you. Kushii is one of those terrifying creatures that you can't escape, even if you try to. In 1973, a group of campers witnessed a long, dark shape slithering through the lake at night. It disappeared in seconds. When they checked their boat the next morning, they found it clawed and dented. A nearby camera had even melted. The campers were found days later, with their tents slashed open, belongings scattered, and a silence that chilled rescuers to the bone. Since then, the tale of the Kushii has spread far and wide. So if you ever see a dark shape lurking just below the water, go as far as you can. Maybe then you'll have a chance at escaping the Kushii. But there's one place greed leads to death, deep in South Africa, where even diamonds aren't worth what's hiding. Our next creature comes from the wonder hole of South Africa. The cave is known to have diamonds in it, but it is also the home of something far more sinister. Those who have ventured in to satisfy their thirst for greed were either killed or traumatized by the creature whom they call the Great Serpent. He is none other than the mighty Grootslang. The myth says the Grootslang was one of the original aquatic creatures created by Poseidon himself. But seeing the wraith he inflicted on humans, Poseidon tried to kill it. However, Grootslang escaped and has been hiding in the cave since. In 1917, a British diamond hunter went searching for the beast's den, but he was never seen again. And the strangest thing about the incident was that his gear was found in perfect condition at the cave entrance, including his rifle, untouched. According to a biologist, the Grootslang could be a giant python species that is now extinct or undiscovered. Combined with fossil elephant remains to fuel the myth. It would make a lot of sense, since giant pythons are said to inhabit those areas. But the Grootslang is much more terrifying than a normal python, since many stories about it have talked about hypnotic voices and a gold-lust madness, said to grip anyone who gets too close to the cave's heart. But moving on to the seventh creature on our list, before the world had maps, before monsters had names, sailors feared a shadow in the sea. That creature is Cetus, and it is one of the oldest creatures on this list. There is no one particular description of him. Some say that it is a huge whale the size of an island, while others describe him as a dragon with scales like armor and a mouth that could swallow ships. Despite the contrary argument on what he looked like, they all agreed on one thing. When Cetus rose, nothing returned. Stories of ship vanishings were often blamed on Cetus. One 18th century shipping log mentions a sudden dark wall rising from the sea during calm weather. Another account from 1732 claims a vessel off the Aegean coast was dragged under after reporting a groaning sound from below, like something turning in its sleep. Modern interpretations write Cetus off as ancient superstition inspired by real animals like whales or oarfish, but old sailors believed it was more than flesh and bone. They said Cetus lived in the deepest parts of the sea, only surfacing when disturbed. But that's not the only huge sea creature on our list. But before you relax, know this. Sailors still whisper about a creature so huge, it doesn't chase, it just waits. In today's time, where modern technologies have revolutionized the way we travel through the oceans, there are places that sailors still avoid, not because of storms, but because of a creature so terrifying that even the best technology today isn't enough to escape it. While it has many names, most people refer to it as the Leviathan. There are no clear sightings of the creature, only the aftermath of its wrath, but that doesn't mean that people have not encountered it. In 1995, a cargo ship crossing the North Atlantic sent a single message saying, mass under hull. Minutes later, its signal was lost. The vessel was found drifting days later, empty, with its steel stern crumpled. The news of Leviathan spotted, followed by a missing boat, is still being reported to this day. Some believe it's an undiscovered species, a creature the size of a small island, and that it lives too deep and too quietly to be noticed. Whatever it is, it doesn't chase its victims. Instead, it chooses to appear beneath you, and by the time you notice, it's already gone. Next on our list is Jörmungandr, a sea serpent so massive that legends say he wraps around the entire Earth and bites his own tail. He doesn't simply lie beneath the sea, he waits, because when he rises, it signals the start of Ragnarok, the Norse apocalypse. On that final day, he'll battle Thor in a fight to the death. Thor will slay the serpent, but only manage nine steps before collapsing, poisoned by Jörmungandr's venom. But this legend didn't appear out of thin air. Tales of sea serpents have echoed through Scandinavian history for centuries. Even in the 1800s, Icelandic fishermen claimed to see something massive, serpents said to stretch as long as an entire village. Today, Jörmungandr slithers through modern pop culture, from God of War to Assassin's Creed. But he's more than just a giant snake. He represents an unstoppable force, something vast, ancient, and inevitable. Does he exist? Probably not. But the idea of a colossal power slowly encircling the world while we remain unaware, that's a different kind of terrifying. Next up is Umi Bozu, a towering figure that emerges when the storm fades, leaving behind a silence far more terrifying. His name means sea monk, and according to Japanese fishermen, if the ocean suddenly turns calm and a thick fog creeps across the horizon, Umi Bozu is near. He rises from the depths, immense, faceless, often appearing as nothing more than a colossal shadow. Some claim he has arms, others insist he's only a massive head. Either way, with a single motion, he can drag a ship beneath the waves. The legend says if a sailor dares speak to him, Umi Bozu will demand a bucket, hand him an ordinary one, and he'll use it to flood your ship. The only hope? Give him a bottomless bucket to confuse him long enough to make your escape. Stories differ on his size. Some say as tall as a mast, others claim as large as a mountain. Today, Umi Bozu haunts anime, horror manga, and video games, always heralding the same thing, a silence heavy with intent. Does he exist? Science says no, but when the sea goes eerily still and the air refuses to move, every sailor in Japan remembers one name, Umi Bozu. The next creature is cloaked in lake mist and centuries of mystery. Meet Ogopogo, the legendary monster said to dwell in Lake Okanagan, Canada. Described as a long serpent-like creature with dark, sleek skin, a small horse-like head, and a gracefully curved body, Ogopogo has fascinated locals and visitors alike for generations. The origins of this legend go way back to the Silks. According to their stories, a powerful lake spirit named Inha-a-ik demanded offerings from those who wanted safe passage across the waters. Over time, this spiritual tale transformed into the myth of a monstrous lake dweller, what we now call Ogopogo. The first major sighting came in 1926 when a group of people claimed to have seen a strange creature breaking the surface of the lake. Since then, reports have trickled in regularly. Shaky home videos, blurry photographs, and countless eyewitness stories. Ogopogo has even earned the nickname Canada's Loch Ness Monster, and there's a charming statue of him in Kelowna that draws plenty of curious tourists. What could Ogopogo really be? Some suggest it's a giant fish or perhaps a prehistoric species that survived unnoticed. Scientists remain skeptical, pointing to misidentified waves, driftwood, or light tricks on the water. So far, no definitive proof has surfaced, but who knows? Maybe one day, someone will catch a glimpse of something that rewrites everything we think we know. And that brings us to the last creature on our list, the Kraken, a sea monster so dangerous that seeing it was seeing death itself. This isn't just some oversized squid, we're talking about a monster the size of an island, with eyes like massive glass panes and tentacles long and strong enough to crush ships like toys. According to old sailors, if the sea started to bubble and churn, you'd better get out fast, because if you actually saw the Kraken, it was already too late. It was so deeply feared that early explorers even marked maps with warnings, here be monsters. But here's where it gets interesting. Giant squids are real. They were only captured on film for the first time in the early 2000s. Before that, only scattered pieces, strange scars on whales, and a whole lot of terror-filled guesses. Today, the Kraken is everywhere, in movies like Pirates of the Caribbean, video games like God of War, rum labels, and even music videos. It's a symbol of the unknown, and it still gives us chills. Is it real? Maybe not in the way the legends say, but with the ocean covering more than 80% of the planet, and most of it unexplored, it's hard to say for sure. Maybe the Kraken never left. Maybe it was just waiting. So tell me, which of these monsters do you think is still watching from below? Drop your theory in the comments. And if you're brave enough, hit like and subscribe, because next time, we're diving even deeper.