Thanks to Zell - @jboimler , Francis - @Col_Mustard_Ret , Drog - @Bearberry , Alex - @orestotel for playing through the Apocalypse Annex.
With funds and food running short, Rougher approaches our heroes with a scrap page “recovered” from others of the group at the Golden Cockerel, a page from the Great Red Book marked with dwarven sites from the time of the elven invasion. He points out that all the other sites on the page have detailed catalogs of the contents but this one does not - it must be still sealed and therefore full of treasure! The site lies in the Ditch of Serpents, up near Appollonia - familiar terrain, Rougher assures them that no doubt the job will be easy
Sceptical but hungry our heroes hitch a barge ride up the river, noting someone tailing them as they leave and boarding another barge behind them. Laying a false trail that they disembarked at the end of the day at the Rugged Hearth, the riverside inn, they travel on a little more and disembark at the nearest point on the river to the place they seek. Hiking through the forest to the edge of the Ditch of Serpents as night falls, they spy campfires and move towards them. Finding some common folk from Appollonia in religious festival costumes camped for the night they join their camp.
Asked if they shared their dreams about the New Sun, our heroes lie that they do, put together the Appollonians tale with the festival cooked up by others from the Golden Cockerel a month previously and in the morning tell them they have had further revelatory dreams and lead them to the mapped site.
After some searching and more digging the find a stubby archaeolith tower, force the door and descend into the pitch blackness. Natural darkvision and gifts from patrons and deities furnish all the party ability to see in the dark but still it is disquieting as they descend. A spiral stair opens to a great ramp, both stained with ancient blood, watched over by a bastion. At the base of the ramp they find another door into darkness so complete even their gifted sight fails. Alek ventures in and plunges from the tilting blocks of the bridge into the frigid pool of liquid darkness beneath. Hauled back out by his comrades, Zell draws on his tabaxi gifts and boons granted by all his comrades and sprints across.
Locking the bridge on the far side lets the rest cross and they find a barrack room and a sizzling mutated goblin corpse. Poking at it a bit Zell consults his patron and is told this thing is anathema. Covering it with a blanket and trapping it beneath a chest, the party proceeds upstairs to the spiral library. There they find a shelves packed with scrolls that they figure must be valuable and start stuffing them into their bags. Distracted, they are ambushed by two more mutated goblins, these blazing with sickly light. Tipping a shelf and then casting back their physical forms before banishing them entirely, the party wins some quiet to further explore.
At the top of the library, the top of the bastion they had seen from without, they find a dwarven planning station and glean snippets of the Membrane Wars and the infectious light of a strange sun that spreads to herald its coming. The also find notes that this place is a containment unit and sigh as they realise the have to check whatever it contains is still there.
Fetching buckets of liquid darkness from the bridge room they proceed past many disturbed warning signs and find a pair of mutated goblins gnawing on the biomechanical roots of a great dome within which liquid darkness sloshes. The damage from the gnawing causes brief gaps in the darkness and when those capture the light of the goblins, the chamber blazes with the sickly light. Our heroes shelter beneath a blanket tetsudo and chase the goblins with mage-handed buckets of darkness as Zell stays out, braves the light and acts as spotter.
Finally a mildly irradiated Zell guides the others to dousing the last goblin with liquid darkness and they set to work Mending and Healing the contraption before retreating and shoring up the damaged barriers.
Back at the surface, with flasks of darkness and pockets full of scrolls, they exhort the New Sun cultists that they have been successful, that their work today will cause the New Sun to rise tomorrow but they must never speak of this place. Highly persuasive, the cultists are raised to a pitch of fanatical devotion and vow to take the secret to their graves.
Everyone gets 160gp after fencing the voidskin scrolls to collectors, re-provisioning the Golden Cockerel and making sure Fluffy is fed. You may also keep two spell scrolls with any cantrip or 1st level spell on them, recovered from the spiral library.
A downtime option (10 days) is now available to “Shore up the Darkness” and return to the dwarven bastion to seal it up more permanently.