The magic angel sword bathes them in a gentle glow of light. It feels more like a Virtue than like whatever he did to Savamelekh. 

Yeah he figured.

Onward.

The stairs lead out into a half-collapsed hallway, where a lilitu, flanked by a pair of abrikandilus and accompanied by several dretches and cultists, stands on the opposite side of a small chasm. 

(A typical lilitu would be less likely than a vrolikai to stun a veteran paladin, but not every lilitu is typical.)

"What's this? Do we have guests?"

There's, uh, really no point in responding to that, is there? But he's a melee guy so the chasm is going to bring him up short.

"Minagho, you wench, get over here and face me like a man!"

"Like a man? Really? Staunton, darling, you of all people know that isn't true." She laughs. "If you're so eager to relive our trysts you could have said so! You know I would never have eyes for anyone but you."

"Shut up!"

"I suppose, if you're so eager for another round, I could oblige you. I'm sure you'd rather be somewhere more private than this, though."

She waves her hand and disappears. An instant later, the chasm vanishes as well, replaced with a damaged but functional hallway.

If they are not immediately having a pitched battle he's going to Create a little water to see if it goes straight through the apparent floor.

The water makes a little puddle on the apparent floor, behaving perfectly consistently with the floor being real.

The demons take this as their cue to attack! How does Blai feel about an abrikandilu attempting to destroy his shiny new armor?

Negatively. But that does not matter. What matters is that he is engaged with an abrikandilu now and hitting it with his mace as hard as he can.

Ow! This abrikandilu is beginning to think that Miss Minagho did not have its best interests at its heart!

Eventually the demons are dispatched. Two of the crusaders are dead.

"Inheritor, take their souls." She'd like to say a longer prayer, but they're in a hurry, and that wouldn't actually help.

"That was Minagho." She doesn't quite manage to successfully conceal a glance at the dwarf. "She's a lilitu, and very dangerous. She was involved in the fall of Drezen, and we suspect her of involvement in a massacre in Kenabres a few years ago." Pause. "I don't think killing a handful of demons is good enough to explain the Weal half of the result. Staunton, do you have a communal Protection from Evil?"

Staunton is screaming with his face that he would really really REALLY like to smash Minagho's face in with his hammer. "Yes, captain."

Blai wishes Staunton luck in his screamed ambition but can't be too optimistic about it. He has nothing to report at this time.

Onward, then.

They have to inch their way around a non-illusory chasm and squeeze past a pile of fallen rocks, but no more demons attempt to obstruct them on the way to the hallway with the Wardstone.

As they enter the room, they see Minagho supervising a group of cultists. She turns towards them as they enter, timed exactly for the moment the first crusader makes it into the room.

"Oh, Staunton, darling, you came! I'm so glad you could make it."

She places one hand on the Wardstone, and the air grows thick. Trying to come closer is like walking through knee-deep mud. She drums her fingers on the Wardstone, and a chorus of incomprehensible, desperate screams rings out.

"You know, it's the funniest thing. All these years, crusaders wept every time a Wardstone was lost — but it turns out those forts were the lucky ones! Why, when we finish with this one... well, my dear, I'm sure you understand how a single point of weakness can be enough to bring down a fort. The working that connects the stones to one another is just so fascinating, really beautiful work. Just think how much more beautiful it will be when we turn it into a weapon of the Abyss!"

She waves her hand, projecting an illusion of the Wardstone line. First one stone explodes, then another, then another, until eventually the whole illusory line is nothing but smoke.

These theatrics are basically wasted on Blai, who by now has come to the live hypothesis "Deskari reopened the Worldwound and the archmages are busy licking their wounds in private demiplanes" but certainly does not know enough about what's going on to follow what Minagho is getting at.

"You bastard! I'll kill you, or die trying!"

She laughs. "You'd like that, wouldn't you? Die a hero, hope Torag is willing to welcome you into his realm? And I bet the rest of you would, too. But I think it'll be much more satisfying to watch you crawl through the streets of Kenabres, trying desperately to forestall the inevitable. There's something truly special about watching the light go out of a paladin's eyes as they watch their friends die, one by one, and slowly realize that even their gods aren't coming to save them. Don't you think?" Pause. "Oh, but Staunton, darling, if you ever get tired of fighting for your doomed, hopeless cause, just let me know. There's a place in this new world for you, if only you're willing to come back to the one person here who truly wants you."

She takes her hand off the Wardstone. The air lightens, and Blai can move his limbs normally again.

...Ser Tirabade has him on this team so Blai's going to not endorsedly worry about that for the time being. There are still cultists here? Any demons?

Well, there's Minagho.

If he doesn't fancy his chances of doing anything to hurt a lilitu, the cultists are still here, a mix of Baphomites and Deskarans. Minagho is the only demon-per-se visible.

Here swordy swordy sword it is clearly a once per day affair if that. He doesn't think he can do much versus a lilitu and he will engage her if obliged to do so or if someone needs a flank but fancies his chances against the cultists better.

The cultists are much easier targets than a lilitu! Most of them go down in about two hits.

Staunton is going after Minagho! He's putting a lot of power into his swings and this does not seem to be working at all. (It does not really seem like additional people flanking Minagho would actually be enough to make a difference.)