A wall of perfect blackness moves smoothly into the room where they first fought Hosilla, as fast as any human (or neather) can run away.

Oh shit -

Wenduag doesn't even bother crying out, she just bolts for the stairs with the intention of never stopping and never looking back even if she hears Savamelekh Himself, because to look upon his face when He is angry is to die.

She doesn't even notice that the approaching demon is covered in a shroud of darkness, but she does notice that it's likely much more powerful than anything they fought here before. She engages the demon cautiously.

Seeing Wenduag's reaction, he knows they're in troubly, even if he isn't entirely clear on the exact nature of it. 

He'll try to get in front of everyone and cover them, because it seems that he can actually take hits even better than Seelah.

Seelah would like to charge right in but she can't, actually, fight in total darkness, and neither can Anevia or Lann shoot into it to any real effect!

One interesting fighter with something like truesight, and a bunch of rabble who can't do anything.

He can stab her every second and more, with four long hands that can reach all the way around her body if she closes in. The very few mortals who are strong enough survive that for more than a couple of rounds will, instead, die of the concomittant energy drain, if they had no idea they'd be facing him and neglected their death ward. And at the same time he can bite her and sting her with his tail, which confuses the weak of will. And if she has truesight to pierce his darkness and still looks him in the eyes, she has only herself to blame.

How dead is the golden-limbed woman, after a round?

Not particularly dead.

She takes some of the dagger hits, and it seems like the energy drain is working at her, until she lunges at him and lands her own hit, and then she's at full strength again.

Hey, that's his thing! ...but it'd be stupid to stand here trading vampiric touches to see who drops first.

But he has a tried and true way of dealing with crusaders (anyone who kills one of his minions, on the day of the big attack, while wearing that much gold, is probably a crusader): stab them in the minions, that's where it really hurts them, and then threaten them to stab some more.

He flies up to the ceiling of the room, which is conveniently two stories high, and hides the darkness-emanating pebble. The warrior has four minions in the room; are they foolish enough to look him in the eye?

And if they don't want to look him in the eye for some reason, but still want to look at him to aim their puny arrows, how about they look at the sheet of paper with a symbol of death that he just unfolded and is holding over his chest?

He tracks the cloud of darkness as it flies up, and he knows that his companions likely do the same. He feels the wave of death emanating from the now-dispersed darkness, and while it passess around him, he knows it spells an end to everyone around him.

He brought them here, and now they are going to die. He led them, and they followed him to their death.

The worst thing is, he knows the exact concept that can save them. He studied it extensively, when he sought a way to cure his sister that was within the bounds of the Order he was born in.

The absence of Death, that negative space within the enforced rules, ensuring that some things are truly eternal. 

If only he was a god in truth, if he had the power to enforce that Order around him, at least on a small scale –

Something responds. Something that resonated with his heart, and lives there still.

The Light of Heaven glimmers, and shines, and swells into a roaring torrent of golden light that sweeps the room from roof to floor.

There will be no more darkness, it promises. No death and decay. Not here, not today. Only the strength and the splendour of life, the life that is itself the greatest Good as long as it does not serve Evil.

For this one moment, the Light of Heaven blazes.

What the Abyss was that? That little mortal had a mass death ward in her pocket?! He didn't even know that was a thing! And she used it as a reaction the moment she saw him, before his symbol of death could kill the other minions! He didn't know that was a thing either!!

This, together with the golden warrior, is quickly growing from an annoyance to a concern, which is to say: there's a real (tiny! but real!) chance he'll actually lose this fight, if he's stupid enough to keep fighting it.

He is very angry and will become much more angry if he learns these people messed with his mongrels and not just with Hosilla. Luckily, he is an old and wise demon and knows how to deal with that safely.

Greater teleport, to some demons he can safely kill kill kill until he's calm enough to check what the Abyss is going on here.

Some things are too fast for ordinary mortal eyes to track.

Seelah sees a great bolt of light, the same light she saw around Miquella when he picked up the angel's sword, descend from Heaven (*) and clear away the darkness to reveal a great demon; she blinks, dazzled for just a moment, and the demon itself is gone, erased from reality. 

She grips her sword tightly and looks around for enemies, but it makes her feel small and - foolish. Like an ant in the presence of giants fighting, trying to sting their iron-shod feet.

"What. Just happened?"

(*) Heaven isn't really up above us; a ceiling is as metaphorically Heavenwards as the sky.

"I... I think it fled. It had... almost killed all of you, and only Lariel's light prevented it... I'm sorry, we're being too rash..."

He leans on Malenia, exhausted after channeling the light.

"If that was needed just to drive it away it must have been a very strong demon!

"Did you see what kind of demon it was?" Anevia wants to know, because the obvious implication is that it's liable to come back, somewhere Miquella and Malenia aren't.

"And is Lariel's, uh... legacy going to keep doing that?"

"I'm not familiar with the kinds... It tried to blanket us all with pure Death, is that identifying?"

"I don't know, I... didn't expect it to do something like that at all? I have no sense of its power.."

"A 'death demon' sounds like nabasu," Anevia says, "they can fly and generate darkness."

"Nabasu turn people into ghouls and also grow stronger when they do it, and luckily after they've grown strong enough they invariably fuck off - nobody knows why - anyway, instead of seeing nabasu grow infinitely strong, or all of them reach the same strength and stay there, we keep seeing weak ones get stronger and then leave. We thought they lose the power after a while, or maybe they use it up on something."

"A powerful nabasu could kill all of us except the two of you, but I think it would still take it a minute or two. If one found a way to grow stronger than usual... that could be very dangerous."

"There's a cleric spell called death ward that protects from nabasu abilities, but it's fourth circle and doesn't last long, so you're usually out of luck unless you have a strike team prepared for a nabasu or a lot of convenient scrolls."

"Wenduag hasn't come back - Wenduag!" Lann shouts back down the stairs; they're clearly not being stealthy anymore, but there's no response.

"We should look for her. She could be in danger alone. Going back through the rooms we've cleared already should be less risky, right? And we still haven't found sign of the younglings. Maybe they're in one of the rooms we bypassed - there's no way they could have gotten past Hosilla or that demon."

"Unless they've been captured, and watched over by Hosilla."

Lann shudders. "I don't want to imagine what a cultist might want with our kids... But if they met, best to hope they were captured and not killed."

Anevia peeks through the far door. "The construction looks different here," she reports, "I think these are the storm sewers under the city. Unless the cultists deliberately imitated them."

"Let's go back and look for the kids, then."

Going back to the long hall with rubble in its middle reveals no sign of Wenduag.

"We left too many footprints when we came through and fought here. If Wendu was trying to hide her trail, there's no way we'd find it. Hells, if she met and fought more cultists I'm not sure we'd notice the signs, with all the bodies and blood that are here already!" Most of the bodies are in the adjacent dormitory but a couple were cut down by Malenia in the hall as they tried to flee.

"Do you think she'd have gone back to the neather camp? We can check in with them before we look everywhere we haven't been yet."