Beware the Breath Stealer

More than Death itself, the people who live around Hongaka Cave fear only the Breath Stealer. Few live to tell about it, and the Breath Stealer's victims are many. Centuries ago, there was once an elf who loved being underground more than being surrounded by the shade of the trees. His name was Monarias Teleberetten Enkartinio. He explored and mapped caves all over Kos and lived for three hundred years before he discovered Hongaka Cave. Nestled between the mountains, it was difficult to reach on foot, and the entrance was a steep drop. He believed he found an entrance to the Deeplands in Hongaka. If so, it would have been the first entrance accessible from the surface. The first few chambers were easy to navigate. The restrictions were still roomy by cave standards, and over the next decade, he explored the cave and mapped out its rooms as they descended deeper into the earth. As the locals started to investigate the cave, Monarias assured them that it was safe and fun.
Thirty years later, Hongaka Cave was a popular site for cave diving, but Monarias still hadn't found the Deeplands. It simply kept going. Intrigued by an elf who enjoyed being underground, Monarias was joined by a couple dwarves and a goblin. They planned to explore an unmapped passage past Larena's Squeeze. It was a tight restriction that even Monarias struggled to get through, and it was twisting and required contorting the body to get through. He'd been through the Squeeze once before and found that it opened up into a slightly wider chamber with another vertical shaft. However, in his last expedition, he hadn't been able to explore that shaft.
The four cave divers descended into Hongaka Cave and past the easy chambers into the more difficult sections. All was well when they reached the corridor just before Larena's Squeeze, and with four of them, there wasn't any room to turn around. Monarias went first and made it through. Some sections required exhaling to fit all the way through. The dwarves were able to stonesing and slip through that way. And the goblin was small and agile enough to fit. They fixed ropes to the rock face to help control their descent into the unmarked section. As always, Monarias descended first into the hole. However, about half way down, he became weak and drowsy. He tugged on the rope to be pulled back up and spend several minutes trying to recover. What he described was that it felt like his breath was being stolen away. One of the dwarves descended next and made it further than Monarias almost to the end of the tunnel.
The rope went slack, and the group pulled him back up as quickly as they could. The dwarf at the end was unconscious, and he had to turn back and leave to make his own way out. However, he struggled to sing his way back through the rocks and quickly became stuck in the Squeeze. Trapped, the remaining three explorers felt that their only option was to descend and find another passage to the surface. There were many caves in the area, so surely it had to reconnect somewhere. The goblin and Monarias descended again leaving just the dwarf to help his friend and keep the rope tight.
On the surface, a few of the villagers who saw the group descend into the cave noticed that the four explorers hadn't returned and notified the village authorities when they returned at the end of the day. With night falling, it was impossible to attempt a rescue mission until the next morning. Another group of adventurers who had experience cave diving volunteered to assist with the rescue and descended into the cave starting early. They were well equipped with magical lanterns and teleportation powder that would take them back to the village if they became trapped.
Back underground, the remaining dwarf had noticed that the line was slack, and every time he called down to his friends, no one answered. He had plenty of food and water, but with the now dead dwarf blocking the Squeeze, fresh air was quickly becoming a problem.
The rescue team arrived at Larena's Squeeze, but the only one who could fit was another goblin. They tried calling out, but it was too far for the sole survivor to hear them, nor could they see the body of the dwarf. It was nearly impossible to turn around inside the Squeeze forcing anyone who tried to enter to keep going. Without being able to tell if it was safe, even the goblin rescuer wouldn't enter, and a new plan had to be devised. They returned to the cave entrance and requested that contact be made with the dwarven clans. A cleric to Hathchan might be able to meld with the stone to pass through it like water, but it was too dangerous for any of them.
It took another two days for a cleric to arrive at the scene, and by then, they assumed the worst that this was a recovery mission and not a rescue. Back underground, the sole survivor pulled up the rope only to discover that both of his friends had come loose and fallen. There were tears and cuts to the rope, and he could only assume the worst. The dwarf cleric was guided all the way down to the Squeeze, and she slipped in amongst the rocks singing them to do her bidding. One by one, she was able to rescue the bodies of the two dwarves, but the other two were beyond reach. Even through the stone, the closest she could get was to a knife that landed on a ledge. The air had a sickly sweet quality to it, and when she returned a final time, she announced that they'd been eaten by the Breath Stealer.
A memorial was held for the lost explorers, and the people who Monarias the best said that he died the way he would have wanted. In a cave. There were prayers to Hathchan to help guide the souls back to the surface for the goblin and elf and then back to the stone for the dwarves.