The layout of these ruins is really confusing. It's not very clear what any given part of it was meant to be, and that's not helped by the cave-ins, which probably account for the majority of the city in terms of area. The most consistent explanation for what the place he's currently in looks like is that it's probably a proper dungeon of some kind, or maybe tombs. And it's not like people left enchanted items lying around in tombs, so Ruby's got his work cut out for him.

Eh, that's fine. It's easy enough to retrace his own steps if necessary, and he is a mage so he can detect magic as a primitive action and doesn't have to rely on sight and trial and error. Of course, anything that's still around after thousands of years will most likely have its magical aura greatly diminished, but what can you do.

Actually, scratch that: there are enchanted items lying around, it seems. If he's looking for weak magical signatures he will, in fact, find some. There's an enchanted ring over there. And another here, next to an enchanted necklace and earrings. And here's an enchanted dagger next to a pair of rings...

...oh. Oh that's. That's probably where the people trying to defend themselves from the sack of the city died, isn't it. After thousands of years even the skeletons would've turned to less than dust, even somewhere cold and dry like here.

Wow, that's... dark.

But actually here's an enchanted item that isn't lying around somewhere someone probably died! There's an elaborate stone carving in a wall with an amulet inset, almost in a place of honour.

...plot item. He's calling it.

He grabs it.

There's a sudden noise from the direction he came from.

Told ya.

"What was that?"

"The plot." He starts retracing his steps to figure out where the noise came from, exactly.

And it seems like a magical barrier has appeared cutting him off from whence he came.

On the other side of it, Tolfdir seems to have caught up with them. "What in the world happened?"

"I grabbed the plot item," Ruby explains, gesturing at the amulet, "and the plot started to happen," gesture at the energy field. "My guess is I have to wear the amulet and then something will happen and I'll be able to advance."

"Young man, you should not be treating this like a story. There can be real danger in these chambers."

That is also true in stories, he doesn't say.

"I'm just joking around. But my guess is still the same."

"Yes, mine as well. This is probably some sort of sealing mechanism meant to ensure no one explores past this barrier that whoever is on your side of the barrier doesn't know about, and your amulet will allow you to explore ahead."

"Yeah, that makes sense. Can you take down the barrier from where you are?"

"Probably, but I would guess it should be easier to do it from the inside. Try returning that amulet to where you found it?"

"Can do."

He can do.

The barrier does indeed come down, and Tolfdir crosses it and joins him. "Take the amulet again and try to figure out how to keep exploring; I'll work on disabling the barrier from this side while you do."

Reasonable enough. Ruby grabs the amulet once more then puts it on to see what happens.

What happens is a slight distortion in his vision—no, not vision. His sense of space? In the direction of the wall he got the amulet from.

...huh. The wall is fake, in some hard to define way. Feels like if he does a little magical push...

It gives way and allows him to step through.

Erandur can step through, too, and as soon as he does he activates an armour spell on himself. "We should be careful. Whatever was hidden by this mechanism is likely to be protected by more than just that."

"...not wrong." Ironflesh and then the Dremora from the staff take care of being battle ready and then they can move on.