White Plume Mountain has tentatively been identified as the “feathered mound” mentioned in the poem. Sages further agree that the “K” signature refers to Keraptis, but most insist that the writer must be an impostor. After all, who can believe the note really comes from the magician of legend after 1,300 years? The former owners of Wave, Whelm, and Blackrazor
have each outfitted a group of intrepid heroes to take up the challenge. Your party is one of those groups. 

When Riikan Dack, a wealthy collector of rare art objects, hired you to recover a weapon stolen from his vault, he offered your group 12,000 gp—a reward sizable enough to dissuade you from asking too many questions. He showed you the boastful note left by the thief—supposedly an ancient wizard named Keraptis—and told you that his sources had pinpointed your destination (the “feathered mound” named in the note) as a volcanic peak called White Plume Mountain. Days later, you found yourselves scaling the south slope of the mountain. You soon located an entry tunnel leading into the rock and emerged in a cave that actually seemed to breathe, exhaling a large cloud of steam and then slowly inhaling again, like a man breathing on a cold day.

Your party has been tasked with retrieving Wave, a trident of immense power and worth. Riikan Dack also informed you before setting out that he's sure the owners of the other weapons, Whelm and Blackrazor, that were stolen would be willing to pay just as much should you choose to retrieve the other two weapons. 

Heading into the cave, the cavern floor was covered with muck—obviously a byproduct of the condensation dripping from the walls and ceiling. Hidden beneath this mud, near the back of the cavern, you discovered a simple trapdoor set with an iron ring. And now, below the opening, a square vertical shaft beckons.

 Taking Jak's words as sufficient enough approval to proceed, Brocc hustles his way into the nearby cave ahead of the others with confident strides. And when he does reach the trap door, it is with a gusto that he opens it to see the darkened depths below it. "Yes, yes, a fine kettle of fish, this one is. Nice and fair it is, I do dare say." He looks back to the others again, motioning to hurry along before turning back look around for a ladder to start the descent down. 

If none is apparent, he breaks out a length of silk rope, and braces himself against any raised lip; having chosen to hold on and let others climb down it. If the drop however is no more than 5ft or so, hops down with a "Terry-ho!" into the shaft.

 Watching as Brocc descends down into the depths below, Jak cocks a grin at his two remaining companions. "May we all be blessed with such boundless enthusiasm." With a half shrug to himself and the group, he follows his gnomish companion through the trap door.   

As I see jax go through the trap door i decide to go through next.

After a short drop you land on a metal grate that leads you down a rusty metal staircase spirals down into warm, humid darkness. The stairs seems to vibrate slightly, as if in tune with some inaudible subterranean rumbling. The foul wafts up filled with a mix of smoke, mold and damp. Below you can see the glow of torches or lanterns, giving off lots of smoke. The walls are damp and spotted with green and white patches of fungus and algae. Looking down you can see murky water covers the floor below.

As Johnson smells the nasty aroma he pinches his nose closed and descends down the rusty staircase and into the dank cavern. 

As the group passes down the rusty staircase, Jak runs a hand across the wall, rubbing the collection of fungus and moss between his fingers. "More moisture than one might expect at this altitude. Not exactly the ideal summer home, eh? Still, at least the lights are on, so there's a good chance our man is in here somewhere."

Reaching the bottom of the stairs, Jak halts the group before anyone can step into the murky liquid. Reaching onto his back, he pulls out an arrow and holds it out to the group. "Best to test the depth and composition with something less...essential than a foot, wouldn't you all agree?"

Johnson steps forward and says, Here, I'll test it. As he grabs the arrow and dips it into the water until it touches bottom or the murky liquid almost reaches to where his hand is.

Johnson dips the arrow into the murky water and find it goes about a foot down before hitting a hard surface. When the arrow is withdrawn you can see it has some kind of residue on it left by the water.

Johnson, curious about what is on the arrow decides to investigate the residue.

(do u want us to roll with the in game dice or can we use another website?)

The roller here. I know it's messed up but I can still see the formula by looking in your post through your profile.

Give me a nature or survival roll 

19 survival

You can tell it's safe to walk through but you wouldn't want to swim or become submerged in the water. It's not any type of poison you know but the water is somehow tainted. 

Now that you are at the bottom of the straits you see there is a single corridor extending 70' feet ahead before it turns sharply to the left, The ceiling is 10' high and it is 10' wide. The water fills the floor the entire way and looks very calm except for the faint ripples extending from where the arrow broke the surface.

As Johnson turns around and looks at the group he says, So who would like to go first and brave these waters. 

"Mm, yes, yes. Right you are, my out of shape friend. Potentially, a, Mmmmmmn -- what's the word I'm looking for again? Ah! Springs! Yes, yes. Undergound springs perhaps being circulated up or down in some way, I do dare say." Brocc declares proudly as he too stepped up closely enough to at least study the sample. "Strange, though. I cannot recall the last time I've been in a Hot Springs having contained such thick a mass, not counting my own of across." He chuckles to himself before squinting at the gunk.

Once self-assured in the knowledge that nothing was afoot just yet, not that he wasn't already, as the once over was for everyone else naturally, Brocc steamrolls ahead again down the tunnel, grateful that his short stature might spare him at least some of the smog above.

And if it wasn't safe by his reckoning, he'd start tugging at his beard as he ran through a catalogue of spells in mind.

(If I can take a crack at as well from a nature perspective, here you go: Nature: 23.)

(Brocc determines that whatever the substance in the water is effects the nervous system and will, at the least, sap your strength. He suspects continued exposure would cause more severe damage)

Brocc leads the group down the passage. The corridor is clear for the 60' and the water stay at pretty much the same depth of 1' the entire way. It is difficult to move through though and you are only able to move half your normal speed. You are also making a good amount of noise as the water splashes around your feet. After traveling the entire length you see that it makes a sharp 90 degree turn to the left. 

Wincing at the party's sloshing footsteps, Jak drops his tone to a low whisper. "Perhaps it would would be best if we proceed with a bit more caution. I very much doubt that we're alone in this place, so we should endeavor to maintain some element of stealth." He looks pointedly at Brocc's clunky plate armor.

Dropping into a low crouch as they approach the bend, he moves up to the front of the group. "Allow me to ensure that there are no nasty surprises for us up ahead." Moving as quietly as he can in the murky water, Jak moves to peer around the corner, keeping a keen eye out for traps or pitfalls as he goes. 

Jak, give me a stealth check with disadvantage.

(Lol, fair enough. 24 )(Wow, gotta love that +9)