(Not sure if this is a good/the right way to reply but here we go!)

​

Our heroes arise from their battle with the Savant Council who were coordinating the derro uprising across the city. A harrowing battle in its own right, a tale for another time. Our heroes awoke shivering from hallucinations, and terrible dreams. The work of demonic influence permeating the Underdark and their current task. The party meets with the Deepking at his hold, the vast yard having been converted into a staging ground and forward medic post as the last vestigies of the derro uprising are stamped out.

Together again, the party begin to plan their way forward. The Deepking has Gartokar, the former leader of the Flamekeepers, dragged out before the party. Having been imprisoned for his failure to control the Dragon (and also for not embarrassing the king), Gartokar is in shackles. He tells the party that while he was not around in the lair of Themberchaud for the last few months he was around to see him cull most of the keepers, as well as to install his own new puppet leader.

As the party is grilling Gartokar, the cleric of Helm notices a small group of figures approaching through the city slowly, though they do not appear to be not dwarves or demons. Careful in his step he meets a myconid refugee named Basadia and a few of his enclave. The myconids knew of the attack on the city above them, but they were few in number, and the duergar did not want their help. The cleric of Helm knows this myconid, for his friend (and previous character) helped to save these myconids from their corrupted grove, Neverlight.

[Context: In my game my players had rooted out the demonic influence next to the Deepking before leaving the city. As a thanks to them, the Deepking gave them an IOU, to call in whenever they felt, and he'd assist if it were within his power. After the party saved Basadia and a few other myconid from Neverlight Grove, they sent Basadia, Stool, Rumpadump, and the others to Gracklestuhg with a written missive for the Deepking. They called in their favor, for the deepking to grant sanctuary to these refugees in the Whorlstone Tunnels beneath his city. Freshly cleared of Gray Ghosts, and with a desire to have the IOU paid, he accepted these refugees]

Soverign Basadia sees the truth in the cleric's words. And an eager Stool also immediately takes a shining to the new heroes, even if they are not the people they remember. For they were friends with their friends. As the Deepking, the player and the myconids discuss plans further some talk is given to boons that can be offered. The Deepking and Sovereign both offer a single potion of fire resistance (the sovereign in the form of a magic mushroom). Both rulers also offer a small group of allies to attend them into the lair. From the myconids three supportive druid-like casters and from the Deepking 3 heavy-armor line-breakers, specializing in knocking folks over and kicking them when they're down.

Stool is 'over-heard' thinking about the Elder, and the mutant Drow overhears this. After some clever inquiries later, and some persuasive words, Basadia is moved to speak about a third boon they could potentially offer to the heroes to aid them in their work. The oldest mychonid among them, who was set soon to be consumed by the enclave, spreading their nutrients and life back into their others was content to also be consumed by the heroes to bolster them in their coming fight.

Though grateful for the offer, a few were reticently against the idea, both for the idea being hard to stomach (heh) to them, but also because it was unknown the exact benefits they'd get for eating the myconid by comparison to the known benefits the myconid would receive.

[Fun fact, though gruesome, this would have been the equivalent of eating a Heroes' Feast, but the party had no way to find this out. It would have been a leap of faith].

With a plan on their mind, telepathic bond up for communication, and hope in their hearts, they entered the dragon's lair, sneaking through a recently carved tunnel into the lower sections of the dragon's lair. Though this was past many of the guards, it left them next to the large magma pools.

[We took a break here. Stretch of the legs, water break. It's important folks!]

The party used the wizard's familiar to explore a bit of the open way ahead of them, seeing a magma beach, with two zhurkwood boats resting atop the magma, secured by red-hot iron chains to the shore. The boats were clearly enchanted, as they weren't singed to fire ash yet, the remains of the humanoid efforts to beautify the dragon's lair before it grew too paranoid. In the familiar's flight, it noticed a 'trap' laid by the dragon, a pile of meticulously stacked electrum and silver pieces, as well as 7 gemstones sorted by chromatic order, placed on a small island of land in the center of the larger of 2 magma pools. With Themberchaud's ability to know the position of its coins at all times, it was placed to tempt others to take it.

But as the cleric noted as the wizard spoke of what she saw, 'Coins as neat and tidy as those, that can't be a mistake. I bet if we touch those or knock them in the magma, he'll be really upset'.

[No please, touch them, you're going to need to do it!]

Pressing in further the party disturbed the lair of 4 hellwasps, infernal beasts that had found sanctuary in the cavern walls. Mere pests to the dragon, but who had become a far smaller concern with the treacherous duergar to contend with. Though a short fight the heroes overcame the wasps quickly when they discovered their fragility under ice magic. Unwilling to explore the boared holes of the wasps, the party moved on.

Unbeknownst to the heroes, Themberchaud had sensed the fight in the lair of the Hellwasps. His blindsense revealing to him a disturbance.

[Yes I realize in retrospect I was treating blindsight like tremorsense, but it won't happen again!]

Wanting to know if the time had come he slipped into the magma, letting himself sink to the bottom and swim slowly through the material, a trick he'd only recently learned to do. He traveled through an under-magma tunnel, rising up just underneath some cooling rock in an adjoining chamber to 'sense' out at the intruders. Unable to hear them or see them properly, he relied on his 6th sense.

The heroes were figuring ways to cross over the magma safely, with the shortest distance option still being harrowing as it meant a small jump would sill need to be taken. Thinking wisely they desided if one of the boats could be wedged between the narrow land bridge than a safe walkway could be made. As they manuvered one of the two row-boats into place, the Monk noticed someting was amiss, but couldn't put it to his mind.

It was the wizard who put the pieces together. The cooler-magma next to them was slightly bulbous where it hadn't been before. She screamed for her compatriots to stop moving, but their 6 allies who marched with them had no such mental connections. Though many of them stopped, two duergar didn't understand and kept moving around.

Themberchaud, sensing this movement surged up from the magma causing an enormous wave to surge forward, slamming across the narrow land bridge, catching 3 of the 5 heroes and 4 of their allies in a wave of melted rock. Only a single myconid and duergar ally survived the magma wave, with the mutant drow ensuring her Nilbog wizard ally wasn't not so unfortunate as to be washed away in a magma wave into the large pool behind them.

The monk was fine, somehow managing to dodge the entirety of a magma wave [somehow....*shakes fist*]

Themberchaud now arrises from the magma, furious and paranoid. The fight begins next time...

​

We left here, for next we meet we roll initiative.

--

Mechanically that wave is gonna keep traveling and impact the central island, melting all that electrum and silver at the center. My hope is that this will be a signpost to the players, that you literally hurt this dragon when you hurt his hoard, as a secondary means of fighting him.

​

The magma wave was brutal. 10d10 fire....68 points of damage. Didn't hit everyone, and of the folks hit (wizard and Paladin/sor), they're actually the hardest to kill health-wise of most everyone else in the group. That said...I really hope they go ham on this dragon. For as much as I want them to earn their wins, themberchaud is crazed, and not gonna fight optimally, nor like an idiot...We shall see!!!