She has an intrigued audience.

She draws 'creativity'. ...and translates the symbols for her audience. "If I'd got triumph I'd think it would work normally by default, luck if I did it at the right time or on the right target or trying the right things, endurance if it wasn't going to work - this one I think I can get it to work but I have to do something non-obvious to make it work."

Fëanáro translates. "Huh," he says, "okay. Well. We can be creative."

They choose a location. It's farther south, near a lake, nestled in the mountains. There are locals and Feanaro sets himself to learning their language. They throw themselves at building walls.

Kiri will heat things on demand.

In that case they can have forges up and running much sooner.

They've been there for six days when they are attacked from all directions. Hundreds of thousands of enemies.

...that's. that's way too many. what.

Well. They can cycle people in and out. They can build walls while they fight so there's somewhere for people cycled out to sleep. They can sleep behind walls of the dead who are piling up at their feet.

Kiri has never ever killed somebody before and she knows that every single one of these enemies is fixable if she had a moment of safety near them and there's so many

Well, they're not going to be managing her feelings, though they don't tell her to fight either. They are pretty thoroughly distracted.

that's okay, she can manage her own feelings

and after a bit of delay

orcs start dropping in swathes.

Well, that'll take some pressure off them. More energy for building walls, and building some wholly defended areas where they can get the civilians safely. 

okay good.

Twelve days. Orcs come at them for twelve days.

Well then she will get some sleep in between mass slaughter.

When the orcs stop coming the Elves decide to charge Angband.

That sounds like kind of a terrible idea and maybe if Kiri looks really shellshocked nobody will invite her along.

They in fact will not. They are also pretty shell-shocked, and sleep-deprived, and numb with horror and rage at the Enemy.

Why are they even charging Angband anyway.

Because he sent all the orcs he had at them here, and maybe it's weaker now than it can reasonably be expected to be, and if they can end this now they have to try.

Okay but why now and not in like a week or something.

The Enemy will have had time to regroup.

So will the Elves.

The King has in fact already charged off at Angband. That was probably not wise but the sentiment is, looking at the site of this massacre, very understandable.