Hello and welcome back to Fab Figmentals!

I’m Lindsey Morse, your guide through the realm of curious creatures, magical monsters, and beautiful beasts. Each week on this podcast, we explore a different legendary creature by looking at its history and folklore. Each episode begins with a story, and then we take a look at the creature’s origins and how it’s been portrayed throughout the ages.

In today’s episode, we’re peeking into the caves of Northern India to visit the thlen, an evil spirt that exists in the form of a giant, man-eating snake.

Cherrapunjee is a high-altitude town in the northeast Indian state of Meghalaya. 

The valleys around Meghalaya are covered in lush vegetation, and the area once held the title of being the wettest place on earth. To this day, it holds two Guinness world records related to maximum rainfall in a single year. 

In order to cross the many rivers and pools, you can navigate the forests using living bridges, which the locals create by weaving and molding the roots of the native rubber trees.

Apart from all the rain, the region is also known for its waterfalls, which plunge from forested clifftops, and you’ll also find a complex series of caves that date back to pre-historic times. 

According to legend, one of these caves is home to U Thlen, or “the thlen.”

Under normal circumstances, I think it’s safe to say that most people would do their darnedest to avoid the lair of a known demon snake, but— unfortunately— that wasn’t an option for certain residents of Meghalaya.

You see, the local market took place in a village only accessible by a sacred bridge that crossed right by the entrance to U Thlen’s cave. Anyone wishing to buy or sell goods at market would have to journey past. And sure enough, the snake would be waiting. 

But all was not lost, for the strange thing about this creature is that it could only devour 1/2 of the people passing by. For example, if you walked by with 3 friends, two in your party would be snatched. If you walked by alone, however, you would be allowed to go in peace.

Now, let’s dive into today’s story. In it, a young boy comes of age and prepares for his first trek into the market. Let’s join him as he comes face to face with The Thlen.

As always, please note that our stories are often more Brothers Grimm than Mother Goose. This story might not be appropriate for little ears. 

So, here’s today’s story. It was written by our very own Niall Cooper, and it’s called “The Oath of U Thlen.”


Silent and still, the great serpent U Thlen lay, coiled in his lair. Dank and dark, his cave opened onto the path through the jungle along which all men must travel if they wished to pass from their high mountain glades to the market towns of the valley below. 

It was a good life that U Thlen led. He never hungered, for the poor people of that region, which they call the “abode of the clouds,” need pass the cave each day. And each day U Thlen would have his pick of the meat that scampered by.

So well-fed had he become that he made a pact with himself:

“Those whose path my cave must cross, 

seeing they are void of power, 

my conscience pricks at their great loss,

so only half shall I devour.” 

Good to his word, U Thlen would only eat half of those who passed by, which for a while was plenty enough to satisfy his hunger.

But the villagers soon learned that they could avoid the heavy toll by traveling alone. When they descended through the jungle from their mountain home, carrying their wares for the market, they did so one by one, well spaced out, so that mighty U Thlen would not take them. For if there was but one, the serpent could take none.

And when they climbed back up through the jungle, returning with their bartered goods, they likewise went in single file, out of sight from the one in front and the one behind, so that U Thlen would not harass them. For though the snake was terrifying and a menace to all mankind, U Thlen was also reverent to the gods and would never break his oath.

After years of safe travels, the villagers heard a sound like low thunder coming from the cave, which at first they feared. “Great U Thlen is growling!” They whispered. “He is angry now.”

Though the rumbling echoed loud from inside his cave, U Thlen never, ever came out. And the folks grew confident again, and said, “Ha! That is not the growl of a beast about to attack, but only the grumbling stomach of a hungry old snake!”

And so the villagers became complacent. Traveling in single file, well spaced out along the road … until it became a custom, just the way that that things were done. The villagers forgot about the hungry snake. And the growling was eventually dismissed as nothing but the wind blowing through the caverns.

Tathagata turned 8 years old. He was old enough now to help his family. He too must work in the fields, and gather foods from the edge of the forrest, and learn to hunt. And he had to travel to the village, carrying wares for sale - though he was only small and couldn’t carry very much.

Tathagata had never left the village before. He was very excited to walk through the jungle … and yet, he was a little fearful. The older boys had told him tales of demons and monsters, which he supposed was just teasing, yet they had frightened him nonetheless. And his grandmother had warned him that tigers could pick off a little boy and gobble him up, which he knew to be the case.

So little Tathagata was nervous to set off into the jungle. “When we travel to the market,” he asked his mother, “Why must we go one by one, out of sight of the person ahead and the person behind. The jungle is so full of danger, wouldn’t it be better to stick together for protection?”

His mother shook her head. “That is not our way. It is tradition to go journeying through the forrest in this manner, and we are a good people who honor the ways of our forefathers.”

This seemed like very silly tradition to Tathagata. After all, it wasn’t his forefathers who had to walk amidst tigers and demons - it was him! And he was scared!

So he spoke to his little friend, a boy of the same age named Mukul. Trying to be nonchalant, Tathagata approached him whistling. “Oh, hi there. I suppose you’re going down to the village tomorrow as well.”

“I am. It’s … it’s my first time,” Mukul replied, unable to hide his nerves.

“Oh, me too. It’ll be quite easy, I think,” said Tathagata coolly. “Quite boring, really.”

“You think so?” asked Mukul in surprise. “What about the wild beasts and the monsters!”

Tathagata shrugged. “Hmm. You know, we could travel together. You know, just to keep each other company.”

Mukul was not too sure about this. After all, he too had been told that people in the village always went alone through the jungle, because that was the way it had always been. But, like his friend, Mukul wasn’t sure that this was such a wise tradition. So, he agreed that, yes, it might be better if they went down to the market side by side.

The next morning, the people of the village lined up and set out for their journey, each walking along the path, into the trees, and out of sight before the next followed on. 

When he was in the forrest, Tathagata stopped and waited for Mukul, who was next in line, to catch up to him. Then the boys walked together, with their little backpacks full of wares to sell, chatting all the way about the sorts of nonsense that little boys prattle on about.

Though neither said it, both were comforted by their companionship, which made the dense, dark jungle seem far less frightening than it would otherwise have been.

They followed the well-worn path, fording a narrow stream, hoping from slippery stone to slippery stone, then ducking under low hanging branches. They crossed a deep gorge on a bridge made from the living roots of trees, and stopped to skim stones across a placid pool. 

They laughed and laughed, for it was such a relief that what had filled them with such trepidation the night before had turned out to be a rather enjoyable adventure.

Then they came to a cave. Vines grew around the mouth and stalactites had formed from the ceiling. A low vibration came from the darkness inside. The boys stopped in their tracks. Their bravado melted away.

“What was that?” Mokul asked, taking a step back.

“I … I … think it must be the wind blowing through the cave.” Tathagata replied uncertainly.

The rumbling turned to a hiss, and the sound grew closer.

“I think we should go, and quickly,” said Mokul.

Tathagata nodded and they turned to go. 

“Stay … [dusty cough and a little sinister laugh] … Stay.” Two great gleaming eyes appeared within the gloom of the cave.

The boys made to run, but in their state of alarm, they stumbled.

In that very moment, the huge serpent’s head emerged from the mouth of the cave, the stalactites crumbling against its scaly skin, the vines separating as its snout emerged. A tongue, long as an elephant’s trunk, flicked out to taste the air. “I see a snack is slinking by. Ah, and a young snack, too - all the better!”

Tathagata and Mokul scrambled to their feet, but the snake had emerged from his dwelling to block the path in front of them. They turned to run back, but the tail now barred that way too.

“I am U Thlen. I am the lord serpent of this jungle, and smart men used to fear me. There was a time that even bravest men, warriors and heroes, would not dare to cross my path two abreast. And now, look - the people have grown so unafraid that even two small children defy me!”

“P-p-please, lord U Thlen,” stammered Tathagata. “W-we meant you no offense! We’re just poor villagers on our way to market. Let us on our way and we will never -”

“Let me stop you there, my boy. One of you will never cross my path again, but the other will. For, by my oath, I shall gobble one of you up and let the other go!” And, with that, U Thlen swallowed poor Mokul whole. “Ah, that was a tasty morsel!” said the snake. “But not very filling. And I have been many a long year without a meal. My stomach growls still.”

U Thlen gazed upon Tathagata with a great, black, glassy eye. “Yes, my stomach grumbles still.”

“But … but, you said that you would only eat one of us. And you have just swallowed my companion in a gulp, so … well, oughtn’t you let me go?”

“Brazen boy! You dare challenge me?”

“No, no, I … I just meant -”

“Be quiet, lad! Let me think. Now, if I let you go then you will tell your people that I am still around and hungry. Then they will once again go by my cave one by one, and so I’ll starve again. But if I eat you then you can’t tell them of the danger. That way other young and foolish children will wander by, two by two, that I may eat. So, that’s it! I’ll break my oath just this once. And if the gods punish me for that, well their punishment can’t be any worse than this terrible hunger that afflicts me!”

And so, U Thlen quickly struck and ate little Tathagata, too. 

And he has eaten quite well ever since, for little boys are often apt to disobey.


This story does a great job of taking us on a journey of the U Thlen legend, but there is a key place where it deviates from lore. 

As far as we know, the Thlen never broke his oath. However, the people got fed up with his antics, and they enlisted the help of a fearless loner to rid them of their snake problem. 

U Suidnoh, the hero of this tale, began to travel the market path regularly, and he would bring with him goats and pigs to feed to U Thlen. One day, after he’d gained the serpent's trust, it let its guard down, and he shoved a red hot coal down its throat. The snake thrashed in pain and eventually died. 

In celebration, the villagers threw a party and divided up the meat of the snake to feast on. One woman pocketed a piece of the snake to take home to her son, but after leaving the celebration she forgot about it and ended up throwing it away. According to legend, from this discarded piece of snake flesh many more U Thlens emerged and scampered away to infest the neighboring areas. Dark. 

It’s likely that the legend of the Thlen was influenced by boas or pythons, both of which are found in Meghalaya, but I think it's also interesting to look at the possibility that the creature was influenced by religion. Hinduism is the most common religion in India, and  nagas, a race of serpents who reside in the underworld, are culturally significant and commonly depicted in art. But nagas are only malevolent to humans when they have been mistreated, and while their venom is deadly, they also carry the elixir of life and immortality.

To me, the Thlen sounds a lot more like the snake found in Judeo-Christian traditions. Lo and behold, when I started to dig deeper into the culture of Meghalaya, I discovered that, due to the influence of British colonialism, it’s one of only 3 states in India with a Christian majority. 

And— I don’t know— perhaps it’s reaching a bit to compare U Thlen with the serpent from the Garden of Eden. But there is a quote from Milton’s Paradise Lost that seems written with the Thlen in mind. 

In book 9, Eve suggests separating from Adam so that they might divide their labor and get more work done. In reply, Adam points out that, “solitude is sometimes best society.”

Just to be safe, this seems like excellent advice to heed, should you find yourself in Northern India, on a trek down through the jungle into the nearby market town. 

-closing music-

Thank you so much for tuning in to this episode of Fab Figmentals!

Research, writing, and sound editing are done by me, Lindsey Morse. Niall Cooper assists with writing and editing. Our theme music was created by the wonderfully talented Graeme Ronald. 

New episodes come out every Wednesday. Make sure to subscribe to the show to get new episodes as soon as they’re available.

If you’re enjoying the show, please consider supporting us on Patreon. You’ll find a link to our Patreon page on our website, We have bonus content and stories available for supporters, and as a small new show, even a $1 pledge helps us out! 

If you like learning about creatures that lurk in the shadows, perhaps you’d be interested in learning more about humanity’s darker side. If so, please also check out our sister show, Assassinations Podcast.

Next week on the show, we’re going to look at the Thunderbird, a supernatural bird found in certain North American indigenous peoples' history and culture that can throw lightening and control the weather. 

We’ll see you next time.