Raphael rolls his eyes. He resumes his place in line while muttering:
"Anna short men make short decisions."
Jugg leads the way down the first tunnel to his right; his first impression was correct, it appears to climb slightly (though the slope is not so severe it makes for a laborious climb). Eventually he rounds the bend and sees that even without the benefit of any light source, the chamber is very faintly illuminated in a neon yellow. The source, it turns out, looks like a colony of moss growing on the wall to the left. Streaks of it stretch out along the cavern floor like luminescent tentacles, and from this Jugg surmises the entire chamber must be covered in the stuff when it is allowed to grow unchecked. But Dalvar seemed to suggest the centipedes were carnivorous, so either there is something strange about the moss (beyond the obvious fact that it glows in the dark) or the centipedes (aside from the fact they are each at least as long as a man is tall), or something else is going on he can't quite get a handle on.
Once the rest of the Heroes have gathered in the chamber behind the dwarf, Argus sees the glint of something from within a crack in the stone floor near the base of the wall. He manages to finesse it out with one end of his longbow, not willing to risk rolling the dice on touching the glowing vegetation; once it has been pried free, it appears to be a glass vial, colored an opaque red, with a cork stopper. Snagging it, the ranger inspects the seal; it was closed up with a coating of clear wax, protecting the contents from this humid, moist, earthen environment.
Not finding anything else of note there, the retinue proceeds directly across the hall to investigate the passage in which Feruq defeated one of the latecomers to the centipede ambush in. It remains roughly level as they proceed down the tunnel then turn sharply left, though the ceiling descends as they march until Thunk very nearly has to stoop to avoid bumping his head. This area of the cavern is noteworthy because its walls, ceiling and floor consist entirely of moist earth. Near the northern wall, there looks to be a hole wide enough for one of the monstrous centipedes to wriggle down, and perhaps with some work it could be excavated further. But the party has more pressing concerns at the most, not the least of which is simply mapping out the rest of the network, and they leave it for now.
Returning back to the main thoroughfare and clambering over the now-dead centipede that filled the width of the hallway, Jugg leads his friends down the corridor furthest to the right. It narrows immediately and requires even Dalvar and Raphael to squeeze to make it through; at one point, Jugg is convinced he must either request everyone slowly back out so he can remove his armor or risk actually getting stuck, but resolves to press forward a few more inches and finally wriggles free out the other side. Once everyone has made it through and straightened out their clothing and gear, they can see the chamber is actually quite spacious with plenty of space overhead to stand tall. The northern wall is preceded by craggy stone steps and protrusions that make for a difficult scramble to navigate, but those who make the trek find themselves standing close to ten feet higher than their colleagues who linger toward the entrance.
Thunk discovers a discarded, forgotten heavy wooden shield, its face gouged and splintered and the iron rim dented severely along the bottom. There is also the top half of a broken spear, its point coated in green blood similar to that shed by the vermin the half-orc encountered only minutes before (but this blood has long since dried). Beneath where he found the shield, Thunk finds another potion flask, this one ceramic and white with a gold band around the seal and a darkwood stopper. It would appear whoever left this gear (there is no sign of any humanoid remains) thought to improve their chances by making a last stand amidst the uneven terrain in the back of the chamber. Not a wise move, it would seem, given the centipedes' effortless skill for climbing over any surface; but if the alternative was to risk getting stuck in the tunnel leading to this room and devoured alive with no way to defend oneself, perhaps he or she would have tried just about anything.
The hall leading to the water only has room for one or two Heroes to venture near the water's edge. Illumination isn't really any issue, but a large protrusion of rock in the center of the chamber conceals what lies beyond. Water laps all around it on all sides, and there looks to be sufficient space to move around back behind it; but the depth drops off precipitously only a few feet from the shoreline. Its secrets are inscrutable, given the water's blackness which foils even Jugg and Thunk's darkvision; exploring further would mean treading water you can't see past your nose in, let alone what lies at the bottom or how far below you it is. However, once an intrepid spelunker actually made it to the craggy outcropping in the center of the pool, it would be a simple thing to find hand- and footholds and simply climb up out of the water and around the pillar.
Cataloguing this curiosity for later, the party returns to the main hall and continues due south. This area's slope is actually quite severe, and if anyone lost their footing he would likely slip and tumble the length of the chamber until he stopped abruptly by colliding with the wall. The ceiling doesn't descend at all and the far end of the room is 20' lower in elevation than at the entrance. There is a very narrow passageway leading east close to the foot of the hill, but the final remaining passageway off the main hall appears to lead in the same direction, and Jugg defers to his companions before proceeding. The air coming from both yet-to-be-explored tunnels is perceptibly warmer than elsewhere in the cavern, and would be enough to cause one to perspire if the Heroes had not taken such a measured, deliberate pace as they investigated each room.
"Every normal man must be tempted, at times, to spit on his hands, hoist the black flag and begin slitting throats." - H.L. Mencken
Raphael looks at the fungus, then back to the glowing Thunk, then back to the fungus, then back to Thunk. Finally, he looks to Dalvar.
He begins speaking in Infernal.
"Dalvar, I am concerned regarding what I believe to be the extraplanar origins of this moss. It matches the description of a substance described in the writings of Biglygill Shimmyshins of the Granheim School of the Arcanum in Torag's Pact, who described it as altering the psyche of local fauna. Given the luminescent nature of our simple colleague, I fear his incandescent orifice may subject him to similar increases in aggression and potentially ritualistic behavior."
Raphael grabs his nose between the thumb and forefinger of his left hand, adjusting it in a rather difficult fashion for any man who's nose has not been shattered repeatedly. Continuing in the harsh tones of Infernal, Raphael continues.
"Does your arcane repertoire include methods to monitor or combat undue influence on the psyche?"
Dalvar replies, speaking the same language, "I am a telepath, as it happens." He glances at Thunk, and continues in Infernal, "Unfortunately, I am neither powerful nor especially skilled. Let me think on the matter."
Wæs se grimma gæst Grendel haten,mære mearcstapa, se þe moras heold
Jugg couldn't understand the language, but two of the words stood out: Biglygill Shimmyshims.
"What're ye sayin'? What about Biglygill? Speak clear words, damn ye."
Dalvar replies, "He wrote about the glowing fungus."
Thunk gives both "magic men" a look of distrust.
Raphael looks to Thunk. He speaks Common.
"'ow yuh feelin, Thunk? Yuh feelin' a wee bit lively?"
"Thunk no trust words Thunk no know."
"Aye. Me annae Dalvar use nasty words. We talky men use words likea you use weapons. Butta we trust Thunk's weapons cuz they Thunk's weapons. We don't know how to use Thunk's weapons. But Thunk's weapons is Thunk's weapons. Trust Thunk's weapons, trust talky men's words."
Raphael returns to Infernal.
"Lack of trust could be a precursor to agitation."
Dalvar shakes his head, and replies in Common, "No, this is normal for him. Watch out for him to start using polysyllables."
Thunk stares for a moment, not sure if Dalvar is still speaking in an alien tongue or not. Then he shrugs it off and glances around at the passages, "Where go now?"
"Just a moment, and then I suppose we should see about this last tunnel."
"Oh, did he? Makes sense. Thunk, don't eat the glowy stuff. Makes ye a right arse hole, so I've heard."
He shrugs and gets ready to do some more good, old-fashioned, wholesome cavin'.
After a minute or so, Dalvar indicates one of the potions, and says, "If someone is bleeding out and there is no better option, feed him this. It will bring him to a stable condition." He passes it to Jugg'r, and then says of the second potion, "This is a glide potion. It is useful if you need to jump off of the top of a tower or something, but I doubt we will need it today."
Jugg'r takes the position with a nod and places it in a padded pouch on his belt made for just such items.
Thunk nods at Jugg's explanation, "New magic man eat yellow stuff?"
Jugg's cut his laugh short with a meaty palm and nodded. "Aye, lad. He must have. No worries though. I'll keep an eye on'im." He tossed a wink Thunk's way.
Caving Under Pressure
"We've crossed the burning wastelands, sought out forgotten tombs/Within this shattered planet beneath a broken moon/We live amongst the ruins where cities once did rise/From graves of fallen nations watch hollow eyes" - The Sword, "Fire Lances Of The Ancient Hyperzephyrians"
Jugg leads the retinue through the narrow passage at the foot of the crumbling hill, wielding his waraxe at least as long as it takes to cross into a wider space. It descends sharply, but the party's descent is aided by the earthen walls closing in claustrophobically all around. It would be no small feat to manage to actually tumble down and injure yourself when the tunnel winnows so severely it nearly props you up with no effort on your part. But soon enough the floor levels out and the dwarf breaks through to the other side. Similarly to another chamber elsewhere in this expanse, the walls are solid stone here. An inch or more of standing water covers the floor, which appears to be worn smooth; it may be that any excess runoff ends up here, considering it is further beneath the surface than any other section of tunnel Jugg has seen here thus far. The Heroes now stand well below ground level, but alas, their theory is proven false immediately: the last remaining tunnel must lead into a separate chamber altogether, since the path you took is the only remaining entrance or exit from this room. Furthermore, the source of the heat remains elusive; at this point, everyone but Dalvar can easily discern that it emanates from somewhere above your heads and perhaps further to the south. So far, everything the wizard surmised about this place has proven to be true, so it seems likely returning to the main passage and taking the last unexplored passageway will lead the expedition to the ventilation unit leading upwards into the castle basement.
There are a few other items of note in this chamber, however. It looks as though a handful of hapless victims found their way here and met their ends in this room. Scattered bones and tattered rags bob in the water everywhere, but one item of note catches Dalvar's eye. A red leather scroll tube, capped at both ends, looks to be in pretty poor condition. But a cursory scan of the chamber for magical auras bears fruit - it would appear the scroll inside is still somehow intact. Gingerely inspecting the tube's contents, he opens it and sees that it actually contains a second, slender wooden tube that protected the paper inside from water damage. Slipping the note from its confines, Dalvar carefully unrolls it and murmurs the incantations necessary to decipher magically encoded messages. It is sealed at the bottom right corner, as is customary with religious orders, with the emblem of a crescent moon, which supports the theory that the shield of faith spell scribed above is divine in origin.
Returning the scroll to its wooden container and stowing it for now, the party ventures back through the tunnel, up the hill and out into the main hall. Confident their trek underground is nearly at its end, they silently gather in formation and make final preparations to search for any sign of the maintenance shaft Dalvar believes to be nearby. Jugg takes point yet again, and leads his friends south until the room opens up on his left into a chamber wide enough to support what, he assumes, must be what they have been looking for all along: a wide, squat rusted hulk of a donut with a metal shaft extending up from the center into the ceiling. The chamber is tall enough to support moving and fighting freely, if it comes to it, though the corpses littered in a ring around the metal hulk don't look like they will put up much of a fight. The ponderous ring of the ventilation unit's bulk is marked at even intervals with horizontal scoops, like flower planters, each perhaps five feet above the cavern floor. One would assume this is where the ventilation system at last pushes out the hot air into the chamber, although currently it doesn't feel any warmer in here than it did anywhere else in the caves. It is hot, to be sure, hot enough for everyone but Dalvar to have broken a sweat; but this doesn't seem like the source of the warmth. No, indeed, it is plain to everyone that there must be something like an unchecked conflagration just beyond the cavern wall to the south, which Jugg senses would be nearly directly over the ceiling of the room the Heroes just finished exploring with the standing water. Whatever the source of the heat, it doesn't seem like it's coming from the castle or its basement (or it would be radiating from the ventilation shaft instead).
Jugg, Dalvar and Argus have a clear line of sight into the room, but before the column can advance further, the dwarf and abjurer spy movement among the remains piled around the base of the rusted metal tube. One corpse, in particular, appears to be ambulatory! The skeletal knight, girded as he is in a full suit of resplendent plate mail with a helmet to match, abruptly flops over onto his stomach and lurches forward on the floor. The visor on his helmet clangs open as he bunches his knees under his abdomen in a bizarre attempt to stand without using his hands; this results in collapsing back to the floor and rolling onto his back, less than a dozen feet from Jugg's position. The head seems to loll to regard the intruders and the skeletal mouth gapes maniacally, but then the entire corpse begins to shake inside its armor.
Jugg - 27
Dalvar - 13
Skeleton - 6
Jugg, thinking better of ushering his companions back the way they came or waiting to see what the undead thing will do next, stomps forward, raising his waraxe in both hands high above his head and putting all of his weight behind the blow when he brings the edge down hard on the knight's back. The blow drives his opponent into the floor, and the suit of armor buckles under the dwarf's onslaught. He hears the satisfying crunch of bone as his foe's spine splinters, but is a bit taken aback when the neck cracks and the helmet rolls away from the body. It wobbles and totters across the floor between his legs and finally comes to a rest sitting upright; the skull isn't grinning anymore, its jaw clamped shut as it passively observes its own headless corpse and ponders the inevitability of death.
Dalvar says quietly, "There is something living inside the armor." With no more warning than that, he scowls at the apparel in question, and a very small thunderclap disturbs the stillness of the underground chamber as a tiny bolt of lightning erupts from the center of his forehead. A soft, bass hum emanates from the armor, lasting no more than a second or two.
As if in response, a mass of centipedes is disgorged from the hole in the armor where the neck would be. It is difficult to discern where one of the tiny vermin ends and another begins; they are of the same general coloration as the larger specimens encountered in the cave, but like the rats in the Redwood forest these are moving as a single fighting unit. They spill out in a sea of chittering, hissing death all around Jugg, covering the floor and crawling up over the sides of the walls and adjacent ventilation shaft. The dwarf can feel them begin to creep up his legs, and try as he might he is incapable of swatting or stomping enough of them away.
Swarm - 6
Jugg has taken 10 damage.
Thunk has taken 6 damage.
The centipede swarm has taken 14 damage.
Reeling from the swarm, and feeling a fool for rushing in first, Jugg scrambles away as quickly as he can. "Nope, nope, nope," he mutters as he grabs a flask of alchemist's fire from his ruck sack. He is still muttering as he tosses it toward the horde. Thankfully, the veritable carpet of centipedes does nothing to cushion the glass flask, and it shatters when it clatters to the cavern floor. The bloom of fire whooshes out to encompass the whole of the swarm, nearly singing the dwarf's beard in the bargain; but to his satisfaciton, he can see the flames licking up the sides of the walls, pursuing the vermin trying desperately to get away from it. What's more, it should burn for a few seconds still, and that might be enough to take care of the last of them. Hopefully.
Feruq - 14
Thunk - 11
Argus - 8
Jugg has taken 10 damage and 2 Dexterity damage.
Thunk has taken 6 damage and 1 Wisdom damage.
The centipede swarm has taken 26 damage.
Raphael and Feruq tarry in the tunnel, not even certain what is happening in the chamber ahead but waiting for some indication of what they should be doing (or at least someone moving out of their way) before proceeding.
Dalvar wastes no time, however. In a display of arcane finesse, he perfectly executes a technique he observed during his studies to open a path from one of the planes beyond this realm in the span of a single breath. His words of power reverberate through the cave network, and as his voice and gestures reach a crescendo, the ground beneath Jugg's feet begins to rumble. To his dismay, a glowing red fissure splits the stone scant inches from where he is standing, and it widens to accomodate what appears to be a man made of lava itself. The anthropomorphic, superheated mass of earth and fire made flesh heaves itself out of the gap, rising to its full height (just about as tall as the dwarf, sans mohawk) while the fissure rumbles and groans shut.
In a grumbling language that sounds like steam hissing from cracks in stone while it is ground to dust, the wizard speaks to his new servant. It looks back over its shoulder at Dalvar, then strides deliberately into the swarm and disgorges a startling mass of glowing magma onto the centipedes. Sweat is pouring down Jugg's face now, but the heat isn't painful. Yet.
Jugg - 27
Dalvar - 13A
Elemental - 13B
The centipede swarm has taken 32 damage.
Raphael moves into the room to get a better look at the scene; thinking better of standing out in the open between the swarm and the rest of the party, he quickly shuffles over behind the ponderous bulk of the machine Dalvar was looking for as he watches the battle unfold.
Laughing in time with the staccato rhythm of centipede popcorn, he shouts, "I love tha sound them critters make when tha buggers explode! Play me a requiem!"
Meanwhile, by the din from the chamber ahead, Thunk is missing a titanic bout against yet more of the creepy crawlies; but Jugg doesn't sound particularly enthusiastic about it, and that makes the half-orc pensive. Standing as he is at the back of the line, perhaps it would be prudent to keep an eye out for any more of the larger, easier-to-smash variety that may try to ambush his friends.
Raphael - 12
Argus and Feruq, reluctant to move too far ahead and abandon Thunk in the event the party is ambushed from behind, anxiously wait. They needn't wait long, however, as the swarm attempts to maneuver around the burbling, cracking, popping pool of lava vomited forth by the magma elemental only a moment before. It can't successfully reach out to assault the Outsider and the dwarf without exposing more of its constituent vermin to the blistering heat of the magma, however, and the hivemind linking every individual centipede together to move and attack as one breaks down in a spectacular fashion. Those who can escape the Heroes by finding nooks and cracks in the walls and floor do so immediately. Many are hopelessly mired in the lava and perish instantly. Some withdraw back to the nest the swarm apparently constructed for itself along the perimeter of the ventilation unit from the bones and rags remaining from its previous meals, but the still-burning pool of alchemist's fire prevents the most obvious route of egress. All in all, this is still probably the least appropriate place to leave someone while they are incapacitated for any length of time; the centipedes still have to eat, after all. But the immediate threat has passed.
Victory is yours!
The centipede swarm has taken 44 damage.
Dalvar says something to his magma elemental, still speaking in Ignan, and the creature glides into the floor of the chamber and begins "swimming" through the earth there.
As the elemental goes about its task, Dalvar pokes and prods what remains of the nest at the base of the ventilation unit. He uses the head of his morningstar to sift through the larger piles from a safe distance, fearing both the remnants of the centipede swarm as well as the still-crackling fires which sprang up all around the rusty hulk after the pool of lava and Jugg's grenade did their work.
The wizard immediately observes that rather than being contained somewhere on the skeleton's person, the armor itself that the swarm concealed itself inside when the party first arrived is one of the items his spell picked up on. The suit of full plate is in pristine condition, especially considering the environment the Heroes now find themselves in. He even manages to save what appears to be an exotic folding fan, which opens to display cranes bathing in a lake penned in black ink on white paper. It is a precious piece of art in its own right and assuredly valuable, but it also sheds a magical aura of its own.
Along with a substantial haul of platinum coinage, the final aura Dalvar detected seems, unfortunately, to be emanating from under the now-cooled pool of lava itself. By "cooled," of course, one must understand that it is not cool at all and still quite dangerous to touch with one's bare hands. But the morning star helps out here, with the wizard prodding until he thinks he has struck something solid other the cavern floor. From there, what remains of the splintered wooden shield Thunk found in the other chamber does the trick of scooping and shoveling the lava out of the way to reveal a heavy steel shield, similarly immaculate to the armor. Actually, it looks like it may have even been crafted by the same artisan and appears to have been part of a matching set.
Jugg wipes some sweat from his forehead and sat his ruck on the ground. "Here." He hands Argus and Feruq a bottle of Alchemist's fire. "Keep it handy."
Somehow, someway, the swarm had proved to be much creepier than the much larger variants. Those were easy; swing a blade and watch them come apart. The swarm, however, needed to burn and he didn't have a whole plethora of options when it came to that.
He made sure to keep one for himself. He also had a good amount of acid to go around should anyone ask.
Something about the fan caught his eye. He would never admit it out loud, but he found it supremely beautiful to look at.
Feruq takes the flask and slips it into a pocket inside his shirt. He has a sympathetic look for the dwarf. "It is being very..." he searches for a few seconds for the right word. "...icky down here." His choice of phrasing might be taken as absurdly out of place to his normal demeanor in a potentially humorous way.
Jugg eyed him for a moment before shaking his head and nodding at the gesture of compassion. "Aye, lots of creepy crawlies that need killin' and burnin'."
Argus meets up with Jugg before he can close the distance and applies a dry weed from his robe. "This will help leach out the venom, hopefully before it can do much more."
"Many thanks," said Jugg. He wipes more sweat from his reddening face. "Thinkin' it won't be the poison that gets me though. This damnable heat, ack!" He takes a pull from his waterskin and pours some on his head.
"Aye, the 'eat's no good 'ere." Raphael smiles behind his matted greasy hair. "At least it ain't Avernus thah!" He chuckles. "Theh say it rains firah and tha 'eat don't cause no devils no mind! I remember jus' an 'our ago when tha rain was a comin dahn 'eal 'ard! I wouldna mind a tad bit o' that nowah!"
He pats Jugg on the shoulder.
"Nice work wit da crawlies."
"We will cool off shortly, no doubt," Dalvar replies as he investigates the machinery in the center of the chamber. As an afterthought, he mentions, "The armor and shield are both magical. Nothing extraordinary, but they are of good quality, if basic. Better than anything you and Thunk are wearing. And the little fan produces a powerful gust of wind if you say 'feng' whilst holding it. All worth keeping, whether we sell them or one of us uses them."
He makes no move to pick up any of the items in question, absorbed as he is in his examination of the contraption responsible for ventilating Parlfray Keep. Dalvar himself looks as cool as an autumn morning.
At Raphael's touch, the worst of the damage done to Jugg's legs and feet is alleviated. Indeed, whereas before his lower extremities were pockmarked with tiny, bleeding lacerations, the wounds appear to have closed up entirely. What's more, in the moments after the sudden, frantic battle against the swarm of centipedes concluded in the party's favor, Jugg has had time to notice that the tingling in his fingertips has mostly abated. He recognizes that he is not in top form, and attributes that as much to the envenomed bites dealt by the ravenous vermin he and his companions just exterminated as to the sweltering heat; but it's nothing a few days won't remedy, assuming he finds time somewhere between now and then to actually close his eyes and get some rest.
While Jugg is busy pondering his numerous maladies, Dalvar goes about the process of examining the rusted iron structure in the center of the chamber. This is indeed what he must have been looking for, though now that he has finally laid eyes on it, the wizard doesn't recognize it at all; if he didn't already know it would be here, seeing it for the first time he would have no concept of what it is or what purpose it serves. No matter. A cursory examination of the base of the donut-shaped structure close to the floor reveals that a combination of lava and the alchemist's fire igniting small piles of human remains here and there packed densely alongside the ponderous structure has weakened it considerably. It might require the use of implements to do so safely, but peeling away a section of the plating to allow one to crawl inside should be simple enough. From there, unless the interior space is entirely filled with channels and tubes Dalvar is unaware of, there should be ample room to stand up comfortably inside it and take a look up the shaft.
While Jugg'r, Argus, and Raphael are working out a way to split up the party's stock of alchemist's fire, Dalvar beckons Thunk over, and points out the weak spot in the iron contraption. "Do you think you could smash this open for me?" the wizard queries.
Thunk walks over to the wizard to examine the machine. He shrugs and nods, "Thunk could smash."
"Please do, then. We will need a hole large enough to allow us to crawl inside," replies the wizard.
Thunk shrugs and hefts the old shield as an impromptu shield and brings it down to bash the indicated spot.
It doesn't take long for the fire that started around the base of the ventilation unit to burn up the last of the remains of the centipedes' previous victims. Dalvar also scooped most of the cooling lava away from the structure in the process of recovering the shield, using the broken shield Thunk has since deployed in forcing entry up the shaft. That leaves the half-orc plenty of room to ply his trade: carrying stuff and breaking stuff.
It is loud and sweaty work, but a simple enough task for Thunk. The sundered shield has since splintered into a single wooden wedge, about a third of its former surface area, and still ringed around the perimeter with iron. He applies this surface to the rusted hulk over and over again, eventually cracking the exterior and punching a wide enough hole to peel the metal back away from the center of the weakened section.
He's trying to be careful, of course, because even a dullard could see that the metal where he is breaking through is sharp along the edge. Try as he might, however, he manages to nick his hand during the last of the process of pulling away sections of metal or folding it back out of the way of anyone who would seek entrance. The broken shield, alas, is no more, but it has served its purpose well.
All told, even the brawniest of the Heroes will have to duck to get inside the shaft but the hole is wide enough they don't have to worry about catching their cloaks or scraping their skin on the sides. Once inside, there looks to be ample room to stand up. For anyone concerned that all the racket of dismantling this contraption would have alerted sentries from inside the keep, there isn't a peep coming from further up the shaft.
Jugg entered Thunk's dirty, dark hole and peered up.
"About twenty feet up's the first break off point. Feruq, if ye can get up there and throw down a rope the climbing would be much, much easier fer the rest of us."
Feruq obliges, leaving his belongings in the chamber where the Heroes faced the centipede swarm. He stoops to enter the strange contraption and, shouldering a coil of knotted rope, clenches the sunrod between his teeth. He stands and regards the interior surface of the vertical shaft, finding a stable place to plant his right foot while reaching up to grab onto something above his head.
The monk is an accomplished climber, knowing enough to let his legs do the lion's share of the work. His friends' voices from outside the ventilation unit die away in a muffled whisper as he ascends; even taking his time, Feruq has little trouble finding his way up to the first horizontal branch in the duct in no time at all. To his chagrin, he notes it is a roughly square crawlspace about three feet to a side. Glancing up above, he guesses the other tunnels that branch off from the main shaft are probably about the same size.
Feruq has spent precious little time inside fortifications or even thinking about them overlong, but based on what Dalvar was telling him and what he observed when the company made their final approach to Parlfray Keep, he guesses his friends are between twenty and thirty feet beneath the hilltop. That means he's right about at ground level or just beneath it, leaning toward the latter, by his judgment (though gauging depth underground is not something he has a keen sense of, unlike his dwarven colleague). When he makes a mental checklist of the sorts of things you might find in a castle basement, he comes up with storage areas, additional living quarters for staff, jail cells... perhaps a wine cellar. And, presumably, a chamber to house the exit point for this tunnel.
If he climbs higher and leads his friends to another tunnel, it will certainly mean making ingress on the first floor or higher in the keep (probably via a fireplace or something similar). This one is their last, best chance of sneaking into the castle from beneath the earth, and will mean a tight squeeze, but so must the other points of entry. He understands well enough from the earlier explanation of this structure that these shafts are meant to funnel hot air down below, not people.