"Let us unearth the Halls of Dammerhall?"
"Dammerhall seems like a prudent choice of a safe word, in case we are separated."
"Aye, that sounds like a good password. Before we go after the others, though, there's something I don't know about these body thieves, and that troubles me. I'm wondering how they reproduce...do they lay eggs in a victim, say? Agna, do you have a spell that'll burn the body?"
"Fire isn't my strong suit. I don't know of any way to dispose of the corpse, other than making a cairn if we can find enough rocks."
"Did any of you bring some of those slug eggs?"
"I have five of them right here. Want me to see if we can use one of them to return this body to the stone?"
"Start by dropping it on his head, I think. That's where it's been in contact with the body the most."
Stali urges everyone to get back from the body. Then he carefully draws out one of the giant slug eggs and tosses it at the head of the corpse.
The egg breaks across the body with a wet thump, and the acid within begins to slowly eat away at the corpse. It's made a definite mess of the head, but you're not sure if it would destroy the rest of the flesh.
"That looks like a good start, but it might take all of them or some other means to take care of the rest." Stáli tries another giant slug egg on the torso.
Hilde watches while the acid from the second slug egg eats away at the body, looking for things that might be eggs or larvae of some sort.
"Ugh! This is a nasty bit of business here. I feel for these surface dwellers."
"Yes, I'd rather seal him in a stone crypt someplace, but if these scavengers are potentially using the body to reproduce, that is probably a bad idea."
The second egg does a number on the trunk of the body, and with judicious use of a weapon haft to nudge extant limbs into the red molasses like pool of decomposing flesh and acid you're confident that the body and anything being carried in it is well destroyed.
"Now let's find those others."
"How many more of those eggs did you bring Stali? If we run into too many more we'll need fire, but those'll do in a pinch."
"I have three left. Enough for one more body it seems, but after that we'll have to try fire or another idea."
Backtracking you take the other passage and settle in for another trek. The tunnel wends and wefts with the flow of the rock, but maintains a run mostly East. After near a half day of solid trekking the tunnel slowly warms before widening to a cavernous hollow. Heat radiates from a wide expanse of boiling water, and the air is thick with the pungent scent of salt. What appears to be a spit of rock holds a rocky pier to one side - whose end you cannot see.
However before thoughts of boiling salt water and the pier can be processed... you also spy your quarry. Three humanoids huddled together just outside the entrance to the massive cavern. They appear frightened and exhausted, but over the dull roar of the water boiling they have not yet spotted you approaching.
Agnqa holds up a hand for the others to pause. She casts her cantrip and whispers a Message tot he three remaining humanoids. "Don't be alarmed. I am Agna, and my friends and I have noticed your predicament. And sadly, we've found bodies of more of your kind down here. May we approach and try to assist you? If you whisper a response I can hear you."
Hilde picks up a pebble, puts it into a belt pouch, and then casts light on the pebble.
"Our group is the one who just summoned the light you now see."
Stáli nods to Agna and waits to see if the humanoids respond.
Padrym grips his axe, ready in case the humans have already been taken and confident that they can't see him yet.
Agna's whispered voice encourages a scream of abject terror from the chosen human, which puts both of the others on edge as well. When it is followed by the production of light and presence of unknown dwarves the terror deepens and they back away nearer to the boiling lake...
"We're from the surface. Are you all right?"
Aid another Diplomacy
"I told you,we are here to help. Screaming will alert every monstrous thing down here as to where you are located. May we approach?"
Stáli shakes his head and chuckles, "Sure, we're from the surface and we're here to help. I guess that old saw isn't inspiring confidence. Maybe once we show them that someone knows their way around down here."
If they don't seem to understand Common, Hilde will switch to Undercommon.
The calming nature of Hilde's voice and the lack of aggressive overtones from the rest of the group begin to pay dividends and the blinking eyes of the surface dwelling humanoids in rags begin to grow more at ease. In halting and rasping voice a response comes in Common "We live... for now... don't come close, there is a sickness upon us... it has already claimed some of us."
"We have healers that might be able to help, if you'd allow us."
"The sickness you speak of--tell us about it. It may be that we can help you."
The haggard faces of the humans are crestfallen "Nothing can aid us... we fall one by one... nothing can stop it."
"The screams... they cut like a knife as it sinks in, taking the light from the mind and leaving only darkness."
It's clear that they've suffered for their ordeal and are emaciated and thirsty. Also, upon the pier just beyond them upon the boiling sea you spy what look to be rowboats made of stone floating heavy and ponderous.
"I think we can give you some food and water. Where are you from, and how did you come to be here?"
The faces take a slight hopeful uptick at the promise of food, and look for provision of same. "We were exploring a cave near our village when elves daubed in black took us... it seems like an age ago. We were taken and held, luck saw us escape while they were on the move... we have stumbled in darkness since..."
Agna slowly begins approaching the group. She doesn't volunteer anything about seeing what was probably their groupmates in the other tunnels. She pulls out some of her rations, and offers to hand it over to the humans. "Do you know what direction you came from? Where were these black elves located?"
Nar bristles a bit of hearing the drow were involved. He listens intently on where they were last seen.
Padrym keeps a careful watch as Agna approaches. Although the facts support the ragged humans, it could still be an ambush.
"Daubed in black. Not likely. More of those damnable drow. I wonder how close that route to the surface is? Took us quite a while to make our own way down as I recall."
Padrym sees nothing of concern among the ragged humans, but his preternatural sense picks up the faintest of scrabbling legs in the dark behind him. Spinning to look, he thinks he sees a shadow move a good forty feet distant... but is unable to discern exactly what (if anything) is watching them...
The humans initially timidly approach the rations, before hungrily devouring them. They shake their head "This place defies our eyes and thoughts... I am sorry, but I have no idea. There was a place where the air was thick with water and trees lived... but that is all."
"We understand. It is not the usual place for your people. Unfortunately, we do not know how to get you home. We could get you to a safer location here. That may be best."
The dwarf turns as the humans continue their tale, now alert to the way behind.
"We've been followed."
"How do you know this, Padrym? Are the followers still there?"
"Followed? What do you hear Padrym?" For the first time since coming below the earth, Stali feels a chill sweep up his spine as he looks back the way we just came.
The decrepit humans are fearful at mention of the potential for an underworld encounter and cower as you discuss what may or may not have been seen.
"Just the scrabbling of legs. Something in the shadows back there. Probably another brain beastie."
The boiling sea isn't associated with any of the legends or stories that you've heard about Dammerhall, but your knowledge of the underdark proves that such things exist. The typical sources are either active magma flows, or some kind of breach between the material and the plane of elemental fire.