And several more leap down from overhead.

They can get deflected too. Look, you really can't kill me, I am incredibly powerful, I really want to come to a diplomatic solution but if I can't I will look elsewhere in solution-space.

If things come in, we'll warn them to leave, then eat them only if we're starving or they don't listen.

How will you warn them to leave? No one who isn't a spider is likely to understand your vocalizations.

Jump in front of them, clickclickclick.

Most people aren't going to understand that you're people from that, much less trying to actually communicate. Oh, and are you affiliated with Morgoth in any way? It might be relevant.

Sharp anxious chittering, no answer.

I am not going to immediately start murdering you if the answer is yes.

We don't know what you mean. 

Morgoth is [this person]. He has been hurting a lot of people. Some people think you're working for or with him. I want to know if this is true.

Born here, never left here, no one tells us what to do.

Well, that'll make this easier. Of course "easier" is a relative concept here. Are there any non-spider persons in the forest or near it so as to probably need rescuing?

No.

I'm going to talk to some people about what to do about this. I will be back. Please don't kill anyone while I'm gone if someone wanders too close. I won't ask you to forego self-defense if someone attacks you but if they're just intruding, I will be back soon and can remove them without killing them.

Click click click click click.

That's probably as good as she's going to get.

She flies back to Celegorm's fortress, in considerably more of a hurry this time.

"You're back early. Get bored?"

"Nope. Turns out they're people, and not working for Morgoth, and they're pretty casually amoral from what I can tell but mostly they seem to just want people to stop tresspassing. I thought it would probably be a good idea to explore other options before jumping straight to murder."

"Every once in a while a couple thousand swarm over their borders to eat everything they can before they're driven back, and also their territory keeps expanding. Their - proginator worked for Morgoth, I doubt he has much use for specific individual spiders, except as a constant drain on our resources."

"That definitely sounds like a problem to be solved, but unless they're going to swarm now it still doesn't seem like the best answer is to jump straight to murder. My first thought was that I could put up a wall encircling their territory too tall and smooth for them to get out or for anyone else to get in."

"...you could do that. It has some other drawbacks, namely that if the north is a war zone, which it will be as soon as fighting breaks out again, there's then no way to get west of here without going more than eight hundred miles out of your way, at least for those of us who cannot fly. The spiders' southern border is the northern border of a hostile kingdom that has specifically a policy against letting refugees through in times of need. I don't suppose you could make a giant sealed enclosure that we could travel across the top of, should we need to move a lot of people west?"

"Hmm, maybe. If I put up a giant glass dome--but that would cut off the air--but I could leave tunnels and holes small enough that they couldn't get through--but if I gave it enough traction to walk on that would presumably interfere with the sunlight..."

"You could have a fairly narrow strip that has enough traction to walk on, and still have the situation be an improvement over the current one from the perspective of using it as an evacuation route, and also for the spiders. If you care about that, which - their mother definitely worked with Morgoth, if any of them grow into something like that we will not notice until it's way too late -"

"I'm not inclined to literally commit genocide because someone's ancestor was horrible. I honestly don't think any solutions I could possibly come up with to the situation as it stands are good, but--tell me more about this mother and her hazards, I may be able to build something in to deal with that."

"She fed off light, and grew larger and larger until she could walk across a mountain range, rip all light out of the world, and consume it to grow still more powerful. Were she still around or one of her children to grow to the same size she'd eat the Sun and Moon, which would seriously inconvenience us and also kill all the Men, I don't think they can handle that sort of thing."