Tomas takes the scroll and removes the sheets. They aren't hiding anything of interest.

Julen leads them into the next room.

The center of this domed chamber is dominated by a complex design painted on the floor in dozens of colors, which is oddly unsettling. Broken furniture and other debris is scattered across the room and a faint acidic odor tickles the nostrils, while an overturned bookstand with a large black tome sits near the far wall.

Oddly unsettling isn't great. What does it show to her absolutely standard Detect Magic?

There's a moderate conjuration aura over the design on the floor. Something is strange about it, but she can't tell what. The black tome at the end of the room possesses an overwhelming universal aura.

She winces and loses the Detect at first. She has never seen an aura that strong. She has seen Wishes and their aura wasn't that strong. And it's universal! What has an aura that powerful and universal? There aren't very many universal spells!

It might be a powerful Permanency of some sort. It isn't necessarily a Wish. Calm for now. "Yanor, I would like a second Detect on the pattern. There's something strange about it but I can't tell precisely what. The book over there is certainly interesting, but it has an aura strong enough I could easily be missing something within it. If we must risk the pattern to acquire it, I expect it worth the price. It looks too heavy for a Mage Hand, and I would not wish to test it even if not for fear of the magic triggering something. Transporting it by hand at least does not potentially expose it to unanticipated magical interactions."

Yanor studies the pattern on the floor for some time. "I have no idea what this does. I've never seen anything quite like it before. I don't believe we can reach the book without interacting with it."

"Indeed. Conjuration, so most likely it conjures something to attack us. I would guess a demon. Yanor, it may be worth a Magic Circle, if you do not see a better use for the casting. Protections would certainly be worthwhile, and might even be more effective — a summoned demon cannot physically strike through one at all unless their spell resistance cuts it, I believe, and unlike a Circle it cannot be shattered by forcing it against the demon. And protection against mental control would be useful if this is a succubus or similar. Is there a Communal version you can cast? A second would be cheaper than a third, and possibly more effective here. Tomas, whatever you prefer for combat, including I presume your new potion, before we press into the room. Retreat to the bedchamber for preparations?"

A Protection from Evil wouldn't perfectly oppose the despair spell from the previous demon. It's not the right sort of magic. It would still help, though, and Suggestions or similar effects could turn Julen on the party. That would have no good outcomes whatsoever, and they need to avoid it if at all possible.

"I can prepare communal protection from evil if we wait fifteen minutes."

"That sounds good to me. Being well-prepared is never a bad idea."

Back to the bedroom for preparations. This may well be their last fight of the day, and if not they certainly won't want to be in more than two with their remaining spells.

She spends the time focusing on her magic, trying to tease apart the feeling of a deeper reserve. By the end, she... is convinced she has something more than her original two types of spells. Just like last time, then. She has third circle castings available to her and no way to use them directly, only with metamagic or wastefully.

Well, wastefully is better than nothing. They will hold a Burst of Radiance no worse than a second circle casting, even if she can't see a way to pull in shadow even if there was enough shadow around for that to help with anything.

Yanor prepares a spell or two.

Tomas prepares spells in his eclectic fashion.

And in they go.

"Yanor, the Protection first. Moment buffs after, then Julen walks forward and tries to pick up the book. All weapons out and ready?"

Communal protection from evil. Haste.

Tomas casts a spell, drinks the potion of displacement, and then spits the potion back out into the bottle.

Julen runs across the room toward the book—

The design on the floor flashes brightly!

A large worm-like monster with a hideous face of eyes and hooked jaws appears in the middle of the room. Mental pressure slams into the party.

The horrible creature's aura has driven Julen mad! He stabs himself with his own blade.

Tomas is also not in his right mind. He slices his palm with his rapier.

Yanor babbles incoherently and does nothing.

It slides back a few paces and screams in the party's minds. KNOW FEAR AND DEATH, PUNY MORTALS

Phantasmal Killer.

Julen collapses to the ground.

Its pressure strikes her... but at a bit of an angle. She can work around it, for now.

And only for now. She needs to open distance, and she needs it to not do that again. The room is tall, and this thing is enormous. A Burst of Radiance high enough to catch only the worm, and then she retreats, hopefully out of range of its aura.