Aulë does not swivel around to look at them; Nelyafinwë is thinking helpfully that he does not need to, Valar and Maiar have senses even when they're not in a physical form and the physical forms are mostly accessories, though some of the Maiar get attached. 

HELLO, he says.

Leareth does not show fear. He doesn't show any expression at all; his face and body will be as still as a rock, until he's good and far away and the god is not paying attention to him in particular.

"Hello," he says in Quenya. Trying to Mindspeak with a being like that seems like a terrible idea. 

IT MAY BE A GOOD THING YOU HAVE COME HERE. WHAT ARE YOU BUILDING?

Leareth isn't sure whether that question is completely literal or partly metaphorical or even directed at him. "Protections," he says, if Quenya has more specific words for magical wards then he doesn't know them. "For - people, journey."

Nelyafinwë suspects that's not what was meant, not at all. But he didn't come here for a verdict on Leareth, he has to figure that out himself and he knows the Valar don't know everything anyway, not even when it's happening right under their nose.

DO YOU REQUIRE ASSISTANCE?

"I not know. Yet. Maybe." Leareth is wishing he had prioritized vocabulary harder before he had to talk to a god. 

IT IS MY WISH THAT THE PEOPLES OF THIS WORLD GROW SKILLED AND REJOICE IN THEIR SKILLS, AND NOT TURN THEM AGAINST ONE ANOTHER IN WAR.

"I wish also. Not war. Wish it–" damn it what's the word he wants, "very much. I - try help." 

I NOTICED. YOU WANT TO BUILD SOMETHING. I CAN TELL WHEN PEOPLE WANT TO BUILD SOMETHING. PEOPLE WHO WANT TO BUILD SOMETHING AS INTENSELY AS YOU ARE RARE. I WISH YOU GOOD SKILL.

That is...probably meant to be reassuring, or inspiring, or something. It is EXTREMELY NOT REASSURING IN ANY WAY. 

"Thank you," Leareth says automatically, at least that phrase he's practiced enough that he doesn't need to be capable of thought in order to say it. 

YOU ARE VERY YOUNG AND VERY HURRIED, observes Aulë, and the metal cools abruptly in his hand to make some kind of very detailed machine part. YOUR FATHER ASKED ME FOR THIS, he adds to Nelyafinwë, floating it across the room so Nelyafinwë can take it. 

We are as ever very much in your debt. Allow me to convey his thanks, as he may be delayed in returning here. 

YES. HE MIGHT. 

We can leave, he tells Leareth.

Leareth gets up and follows him and tries not to think any thoughts at all until they are far enough out of range that the air stops feeling blurred with magic and is normal air again. 

Think you'd know one if you saw them? Even if they weren't in a physical form? he asks once they're out of the ravine and back to the village.

:Yes. Absolutely, yes: Leareth had barely been aware of the limits of Aulë's physical form, blotted out by the blaze against his mage-senses like a baby sun. :Unless they were - hiding, in some way I cannot imagine, but I doubt it is possible to hide so much magic: 

It'd surprise me too. They used to make gravity work wrong around them, and the air would get all fuzzy. Some of them have learned to tone it down a little but it took a lot of effort. 

:This is toned down?: Leareth can't imagine being around anything brighter than – that.

He can keep his face level, keep from actually shaking, but in Mindspeech, he can't completely hide that the last five minutes were among the most terrifying of his life– of his many lives. 

He would reach out and give him a hug if not for the fact where he knows and so obviously he cannot do that. Aulë has always been good to us. I'm sorry he frightened you; I don't think he meant to.

:No. I can imagine that he is - trying his best. But...I have not had good experiences of gods: Keep walking just keep walking and once they're back to the village he can Gate them miles away and probably even a god can't read his mind from there. 

I'd gathered. It sounds like we already needed to figure out a way to get rid of bad ones.

There are enough shades of meanings that sentence could hold, that Leareth instinctively skims the surface thoughts behind it. 

The situation in Tirion is maybe more pressing, and plausibly needs solving first so that there are even spare resources to dedicate to anything else, but the situation in Leareth's world is much worse than the one even in the Outer Lands. The Quendi in the Outer Lands die sometimes, and are revived away from their families in Valinor, but Tyelcormo hadn't gotten the sense that was common. They weren't beset by monsters. Their children didn't die. 

And then there's the thing his father had pointed out, immediately, the question - why would there be two worlds - and it all adds up to that they'll need a reliable way of defeating evil gods. 

This is most of what he's thinking about but he has a lot of threads of attention and one is contemplating who he could set up to usefully give Leareth a hug and one is making excuses to his maternal grandmother about the fact they're about to Gate out again without even saying hello.