"Agreed." Krom nods. "Let's head back to the camp. It will take a bit of time to figure out how to craft that wand." The dwarf lowers his shield as he prepares to move out.

Rhogar's grumbles and growls, still seeming lost in thought while studying the wood piece, before finally answering in a slow nod. "Yes... yes, I... Hmm... I feel we'd be cutting it a little close going so far back, if we hadn't already. But, so long as the intent is to set out as soon as the wand or, well, a facsimile of one is completed, I have no qualms with that." Rhogar proceeded to offer the wood piece to Gorrah, trusting her to see it safely secured in his backpack before returning to her usual purchase wrapped about his neck. In the meantime, he'd focus on following after the others. 

You can safely make it back to camp, also you can easily collect some corpses for ashes

Here are the clues, in order

First, shield thy heart with a wand from the Nether Oak. - Tower of Abjuration

Second, summon a flame in the palm of your hand.  - Tower of Conjuration

Third, a burnt palm loosens the tongue. Shed a secret about yourself for all to hear. - Tower of Divination 

Fourth, coax a secret from another. -  Tower of Enchantment

Fifth, quench the flame in thy palm with ice. - Tower of Evocation

Sixth, show thy face to the sky. - Tower of Illusion

Seventh, trace a circle with the ashes of the dead. - Tower of Necromancy

Eighth, stand firm in thy circle of death and consume poison. - Tower of Transmutation

After reaching the camp, Krom removes his backpack, places it on the ground and sits next to it. "This is it, my friends. We are close to the end now." The dwarf then turns towards Rhogar "How do we craft that wand? Do we have to enchant it or will it be sufficient to shape the wood into a wand? I can use one of Moradin's hymns to shape the branch."

(OOC: Above game, couldn't really find any official sources for wandcraft outside of crafting magic items. But as regular focii aren't actual magic items themselves and relatively cheap, I figured the below would be Rhogar's expectations after having crafted magic items and similar in the past.)

Having sped up his pace as the group neared the camp, Rhogar is close to, if not the first to arrive on site, and wasted almost no time upon arrival except for curt but passing greeting to Vellyne and the rest. All so he could sit down, carefully shrugging off his backpack in the process, and break out the wood piece to continue studying it.

"Hmm.... Hmmm.... If the aim was to, ehh, empower it, making it more than just a, uh, focus, then... yes, yes we would need additional material. However, the netherese would not have fashioned their wands from this particular wood had it not have most /if/ not all the appropriate qualities to, uhh, act as a 'channel' for the arcane. Grant me a boon of woodcarver's tools and I could manage the task over an hour or so." Rhogar then finally looks up, and as he did, so too had Gorrah, as the duo had become engrossed in studying the piece. "But, let it not be said that Rhogar Nimbatuul dared to stand in the way of a blessed dwarf inspired!" He said with a chuckle as he held out the piece to Krom. "'specially since these hands of mine have no doubt become clumsy from the chill."

"Perhaps we could setup a small camp fire so that you are more comfortable while crafting this wand." Kazri looks for loose branches that could be used for a small fire.

"I understand little of magic though I think I've picked up some understanding as I have traveled with you all.  If I do understand correctly each school had a tower and the clues perhaps each are powered by the tower?  What i mean is, for example, summon a flame is a conjuration correct?  The only that i don't understand fully may be the sixth.  What does it mean,  show thy face to the sky?  It is the tower of illusion.  So some sort of disguise or trickery? That is what illusion means to me. "

Chill spoke as they settled around a fire and warmed themselves.   He took out his bone tankard and drank warm water and then absently flipped his luck stone.   His ethereal fox companion lay curled at his feet.

"Very well Rhogar, I'll do it then." Krom chuckles as the dragonborn gives him the branch. The dwarf, holding it with both hands, begins the hymn of transmutation.
Krom, places the branch in front of him and using his chisel etches on its surface a series of runes. As the dwarf utters the last word of the hymn, the runes flash with a bright red light burning away most of the wood and leaving behind a polished wand. "Here you go, Rhogar."
"The sixth clue puzzles me too, Chill. It will require an illusion of some sort." Krom says after giving the wand to the dragonborn.

Rhogar accepts the wand, and after spending a few moments studying the finished product together with Gorrah, the two look to Vellynne as if expecting something. But then, they looked away sharply, seeming almost embarrassed by the way the duo fidgeted on the spot. ".. *ahem*... Yes, uhm, the sixth one is rather tricky one, isn't it? Or at least sounds like such. But in keeping theme with plans to substitute poison with libations... or, so I thought was the plan for that one, uhm.... yes, uhh, I'd wager we could perhaps skirt that one either by simply looking up-" He points to the ceiling with Gorrah demonstrating by nearly falling back in trying to look as up as possible. "Or at the pool of water from the melted ice, which ideally should reflect much of the ceiling or 'sky' as the verse suggests. And if that does not work then we'll need to find some artifact capable of casting some minor illusion of a sky to look at. Unless of course, Ms. Vellynne or Xerophon. Which reminds me, how have you two been fairing thus far?"

My apologies.  The 6th clue is “Sixth, hide thyself behind a mask.”.  I'm unsure where i got the other at this point.  I think it was from a pdf guide I had been using.

"The sixth verse suggests to hide behind a mask." Krom adds after a while. "We should have enough spare cloth to make a simple one. Like the ones used by human nobles for special occasions." The dwarf pauses "I don't have the skills to craft a proper mask, but between all of us, I'm sure that we will be able to make one."

"I hope you are right Master Krom. There is also hope that if needed, improvisation will save the day as well. Are we ready to finish this mission?" Kazri starts to pack her stuff.

"Tower of illusion,  mask.  Definitely a disguise of some sort.  Simple enough for that.   As for the poison, I'd say a real poison would be needed.  While you could argue libations can be poisonous it's not really a poison.   I'm sure the level of magic we have seen here we won't be able to trick it with a fake or quasi poison. We'll need the real thing. Unfortunately poison isn't my thing, I don't have any."

Chill added to the conversation

Krom takes out from his backpack the Alchemy jug and patting it replies to Chill "We can get real poison out of this."
The dwarf packs all his staff and says "Let's craft the mask and prepare ourselves to end this eternal winter."

Both Rhogar and Gorrah exchanged sidelong looks, then sighed and shook their head. "As you wish, though in my experience it's less about 'tricking' so much as providing an adequate representation of a concept. As I doubt it would do to show up to a congregation sickened even with magic or antidote readily available, or provide an opportunity for one's rival to swap out a less lethal poison for a more virulent one. But, I digress. Once Master Krom here is finished with his mask, I say we can move on." 

Confident that you understand the clues and what is required for the Rite of the Arcane Octad, you make your way through the broken streets to the heart of the city. Towering above the ruins, a shimmering force field encloses a 1,200-foot-tall obsidian citadel—the central spire of Ythryn—its shadow dwarfing all other structures around it. The air hums faintly with latent magical energy as you approach what appears to be the citadel’s entrance.

An arched strut of dark stone, graceful yet cracked with age, rises from the rubble-strewn district below and connects to a junction high on the central tower. At its base stands a gate—tall, imposing, and engraved with intricate arcane sigils that shimmer faintly with dormant power. You recognize the symbols immediately: the ancient representations of the eight schools of magic. The gate stands silent and still, awaiting the completion of the rite that will grant you entry.

Krom after finishing to craft the mask from some spare leather, gives it to Rhogar together with a vial of poison conjured by the alchemy jug.

As the group finally reaches the arcane gate, the dwarf gripping thightly his hammer and lowering the shield says. "This is it, are you ready Rhogar? I'll be ready to defend you if something try to interrupt your ritual."

"I will check our surroundings. Last thing we need now is unwanted surprises." Kazri asks Oli to sniff the air for intruders.

Kazri Perception: 11

Oli Perception: 21

Though he'd grimaced and glared at the offending object, Rhogar had nonetheless accepted it without further word of complaint, knowing to do otherwise was to waste time: a commodity the fellowship had little left at this point. So instead, he shifted gears and spent much of the sojourn back to the gate making sure he was prepared as possible...

"Hmn. I am.... I am as ready as I'll ever be. And I trust that you and everyone will do as much as they can." Rhogar clapped a hand on Krom's shoulder and smiled. In that same moment, Gorrah flew from the dragonborn to the Tabaxi's shoulder, intending on watching the proceedings from there.

Rhogar then proceeded to step up just a few feet closer to the gate, and after sliding his own treasured staff into his bag of holding, took out the Nether Oak wand.

“First, shield thy heart with a wand from the Nether Oak.” He intoned in draconic before holding the wand over his chest -- over his heart, then waited a few moments to guage a response from the gate. Even if none is forthcoming though, he pressed on, placing his trust in the Weave and in the party's hardwork up to that point.

"Second, summon a flame in the palm of your hand." Using the wand as a focus and through gritted teeth, Rhogar held out his free hand and intoned the word "Ergamos..", conjuring a a ball of fire condensed to the size of a baseball in his hand. But aside from a grunt of pain from the initial burn, Rhogar had been able to power through with the next verse. "Third, a burnt palm... loosens the tongue. Shed a secret about yourself for all to hear. I..."

He paused. Did he even have a secret? Sure, he dabbled with the dance of silver tongues (and almost always to poor effect), but the truth ever found its way to the light. But never had he trafficed in even white lies, as the act of such duplicity ever befouled the tongue and tore at his guts! In a moment of burgeoning panic, Rhogar looked to the others as if hoping to find succor. But what could they do?! -He- needed to be the one to convey...

Then his gaze finally fell on Kazri and... gradually went wide at an epiphany. It took a great deal of willpower, but Rhogar eventually managed to look again to the gate and speak the next words in a shaky voice, but in draconic.

 Rhogar then held his breath, shoulders tensing for a moment or two, before finally relaxing alongside an exhale. “F-fifth, quench the flame in thy palm with ice." For the next part Rhogar simply eased off the flow of magic going into the sphere, so that when he went to press the miniature flaming sphere into an ice ball shaped from some water from a waterskin, the ice would be more than cold enough to douse the flame.

And so on things went with him following the steps to the letter, and using the time spent pronouncing each one to make sure the gate registered the actions (or so he hoped, in any event). By the end he still wore the mask, held the wand, and with one hand still coated in the ashes of dead cultist, waited baited breath...

Con Save(DC ??): 24. (if needed for the poison)

Chill also takes up a position nearby.  He stays close though to support Rhogar as needed.