It's hard to say how many NEs dwell in Teldrassil and if their loss will be so crippling, even ignoring the possibility that the place could be at least partly evacuated before burning completely. They have settlements all over Kalimdor, especially in Darkshore, Ashenvale and Feralas, with other outposts strewn about. There's certainly enough Night Elves to organize an anti-Horde resistance, especially with Alliance support which will be coming given the datamined conflicts in Kalimdor. I very much doubt their will abandon their millennial homeland without putting up a helluva fight.
It'll be an empty farmhouse in stormwind actually
#boycottchina
Lorewise, most of them lived in the surrounding forests anyway. They will simply shadowmeld into the trees and keep fighting for their home.
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^^^^This. Horde cannot attack neutral factions without fighting their own members. What's next? Horde attacks Earthen Ring, Light's Hope Chapel, and Acherus?
"I Am Vengeance. I Am The Night. I Am Felfáádaern!"
Exactly, however, while htey will contiue to fight to claim it back there, they'd have to have a new home.
Broken Isles most suits them - City wise, the most likely candidate is Suramar - whether they will hold the whole city, or the non-instanced portion of it - some sort of scenario where they actually share with the nightborne (which would be a bold move by blizz since that would mean night elves (kal and shal'dorei perhaps won't have the faction conflict bind them as much - ofc the habitation could not be peaceful, it could be forced, with the two groups at a deadlock.
An alternative for a city is a rebuilt Azsuna, which could possibly involve a restored Court of Farondis.
I don't see any realistic option for the night elves outside the broken isles. If the horde totally claim Kalimdor, it is not inconceivable that they would then grab at least Suramar, Val'sharah and Azsuna, possibly Highmountain too - seeing that the nightborne and highmontain have very tauren and night elf zones to feel at home in Kalimdor
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That's true, and a good point, same with Hyjal/moonglade/felwood/winterspring are all Cenarion Circle land, so even if the horde control kalidmr, you will still see night elves around, but they're neutral ones.
The faction night elves are different. same with val'sharah... curerently neutral as well as azsuna and could easily sitill be neutral or allied witht eh nightborne, blizzard would have to change that neutrality if they want to give the night elf faction those places.
but yes, night elf druids /= night elf faction just as ARgent Dawn humans /= Stormwind humans