Then they're finally back at the other end of the hall, which has the promised pool of unexplained blood below another bas-relief of Baphomet's goat-head.

And past that, a large square room with a ritual circle drawn on the floor in blood, a few human bodies lying around, and two dretches.

Oh, these poor wretches. Made from leftover bits of souls, barely smarter than animals. Perhaps they were animals in the first place, or feral Boneyard babies.

They're not even any stronger than some of the guys he killed already, and they still attack the party on sight.

There's no real way to take dretches prisoner. They don't even understand the concept of surrender properly, beyond the moment when someone stops threatening them with a sword. A few dretches evolve something like human-level intelligence, but for the most part they're just walking bags of suffering. 

Of all the demons he's met, it was always easiest to convince himself that destroying a dretch is a mercy killing. Gord doesn't know of anything he can do to make life any better for them, not really.

He aligns his sword with Good, and tries to make it quick.

"What happened here? Did the demons turn on the cultists?"

Anevia inspects the ritual circle. "I think this was a summoning circle," she says. "So yes."

"I wish all evil cultists were stupid enough to summon demons to devour themselves," Lann jokes. Judging by his expression, it falls a little flat even with himself.

"Well, at least that explains what the blood fountain is for. Though not where it came from..."

"I never made it past this room but I think the next door leads upwards. That matches what the prisoner said."

The next door has two keyholes and they don't have even one key.

Anevia tries lockpicking but quickly finds out there are no tumblers or other visible mechanisms. "It might be magic."

Detect magic. "Yeah, it's magic all right."

"Should we try to find Lusilla or her hands? Or interrogate the prisoners after all?" Either option will take time, while the kids are presumably in danger.

Stone shape. The door with its hinges falls out neatly out of the remains of the archway.

"My spells aren't just for healing, you know?"

That is pretty cool! Seelah smiles in relief.

Beyond the doorway, a staircase winds upwards.

"We don't know what's past here. I'll scout ahead. Seelah, your armor is too loud."

Well she's sorry but if the alternative is not having any armor over her chest like mister chainpants over there then she's not actually sorry at all!

Does he trust any one of them without his supervision? Not entirely. But he does trust them to keep each other in check.

"I'll go. If I'm not back in ten minutes, I'm unable to return."

Invisibility. He pads quietly up the stairs. There are lit torches on the walls here too, so he doesn't need Wenduag for her darkvision, which is inconveniently unavailable to clerics.

The top of the stairs opens onto a sort of balcony overlooking a small round room. 

In the room are five young mongrelfolk, an aasimar, and a human woman with one of Baphomet's signature glaives.

And a four-armed demon of a kind Gord devoutly hoped never to see again, or at least not until he had quite a few more spell circles.

Calm down. Deep breath. Deep - no, quiet breath. Easy. It hasn't seen you yet. It has its back to you and the invisibility won't let anyone else see you, so you can still get away.

Gord deliberates whether casting silence with its damnable verbal component will attract more attention than the ensuing silence would solve, decides against it, and very carefully tiptoes back down the staircase.

...where he dismisses the invisibility so he can frantically shush everyone and lead them (quietly) back into the main hall.

"It's a vrolikai."

Out of everyone present, only Anevia knows enough to understand why this might lead to panic, but she also controls her face better than to let any panic show.

Wenduag also knows why seeing Savamelekh might lead to panic! Which means, by Gord's reaction, that the demon is out of their league after all.

...pity.

"How bad is a vrolikai?"

"A little bit" - he holds thumb and index finger half an inch apart - "weaker than a balor. This might well be Deskari's direct lieutenant in the city, if Khorramzadeh hasn't come back."

...oh.

He turns to Lann. "Your kids were in the room with it. Well, I assume it was them. I'm sorry. I don't see how we can save them."

"Damn it. You're sure we can't do anything?" It's agonizing to be told your tribe's children are in the next room with a demon and that you shouldn't go in to help them.

"Yes, I'm sure! Vrolikai are - look. We only ever saw, like, ten of them, in the whole war. I mean the Fourth Crusade," he adds for Anevia's benefit. "They don't leave the Abyss much."

"One of them took the Tenth Infrantry apart. Couple of hundred men, clerics, the lot. Just waded through them like tissue paper. Nobody on the field could do anything until it got bored and went away. The only way to survive was to hide in a deep enough hole."

"Any spells slide right off them, their gaze drives men mad. A hit from it would kill any of us on the spot. I can't sneak past it because it has truesight and even if I could there's no way I could get the kids out."

"It could be an illusion or a polymorph?" Seelah offers, aware she's grasping at straws.