I think Stormwind and Ogrimmar would be the only places that struggle with this.
Teldrassils branches are so thick and just in the way of things all the time, so Darnassus would not even be an option for them, not to mention the sheer height.
Ironforge is a massive dwarven capital that can be locked away, they would have no problem at all to prepare even with years of a siege.
Undercity is as well underground. Yes, they may lose more of Lordaerons ruins, but its not like they would care that much.
Thunder Bluff has so little space that it would be very difficult for the Legion to summon anything there. And if they did, a bunch of angry beeefcakes would just throw them off the edge!
So there you have it. The legion would actually have a real problem if they tried to just attack the capitals. If a place such as Westfall can be defended, Ogrimmar and Stormwind could as well.
Well, Lore Wise, Azeroth is huge, and the Legion might not even know where the "Bases" of major factions are.
Technically, the current invasions in Kharanos and Azshara are upon Orgrimmar and Ironforge.
If we had to concoct a lore-heavy version explaining the current situation, which would be difficult based on the Burning Legion being literally infinite, it would have to revolve around the fact that the Burning Legion is very inefficient, mostly because its a rag-tag gathering of sub-optimal and disobedient minions without minds who are enslaved to power-hungry individuals with logically less perception than democratic masses.
This means not only do they not have the intelligence to accomplish the feat (like knowing where to begin) but they also don't have the organizational prowess. At this rate, every bombardment from a Legion Capital Ship is literally the attack of a Named guy using a single Gun.
They simply cannot get 500,000 fel guards to wear black helmets, build a death star, and THEN shoot alderaan. *erm* Azeroth.
The potential for them to do this during long term siege could become a plot device later.
Probably because the "players" who have powers always save azeroth. It isn't the Alliance and Horde NPC's that are going to defeat the legion. It is the raiders in mythic gear who will. Whole other ballgame. Get at me, bro....
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Starships also don't exist yet you act like they do, lol
As ship that is stationary can be hit by a cannon if the gun shooting that cannon has the power to launch it that far and those legion ships that stay in one place aren't going to be hard to miss.
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Show me one example in history where alien starships are hovering above the earth. Get it?
I mean, just have a bunch of us mages gather in the city and focus a giant pyroblast at the ship.
Pretty simple.
Like a spirit bomb, but a pyroblast.
Teldrassil is a tree. Thunder Bluff is located on the actuall bluffs. Both would be extremely vulnerable if bombarded by giant fel fireballs like the one Gul'dan summoned in the Broken Shore cinematic. Same goes for Stormwind and Orgrimmar really since they don't have any meaningful defense against such an attack.
As for Ironforge and Undercity, these capitals may endure, but will still be buried under tons of rubbish.
Now other capitals have a better chance - Exodar may easily escape since it's been repaired, Silvermoon and Dalaran have enough powerful mages to defend their cities.
it makes as much sense as archimonde getting beat straight up by a small army of mortals
How joyous to be in such a place! Where phishing is not only allowed, it is encouraged!
Well, that's just not true. A couple examples:
Azeroth has mages, who could bombard the ship with spells. It has shamans who could call down thunderstorms and weather effects.
We obviously have flying machines, gryphon riders, wyvern riders, gunships and all sort of other types of troops that can fight in the air.
Ultimately, since the Legion is going to destroy everyone, some flying creatures would probably be willing to help us.
And - of course - we, as players, can fly too.
short answer: not a damn bit of difference. just a different set of priority targets.
do we have weapons that can point upwards? yep.
missiles? check.
High Explosive (round shot)cannon shells with cannons that can be pointed up near vertically and still shoot targets two plus miles up? no just no.
lol at the king idea.
even if any of our projectile weapons are magically augmented to reach incredible velocities (manufacturing issues aside) we arn't going to scratch the paint/hull with the shield system they have which is obviously anti biological, anti energy/magical/laser/graser/mazer (pick a *^#%ing energy weapon), anti concussion/missile/physical, oh and anti radiation shielding systems. AND HULL ARMOR.
it is a drop ship. it is designed for hostile planetary assaults with hitech civilizations not being happy to see them, when the Legion wants to actually capture a planet intact and not just throw c-fraction velocity random in-system objects down those poor sods collective throats. the Legion sends these little "hi i'm a multi-dimensional beacon/ship that my buddies can use to lock on, portal in, and make everyone else have a baaaddd day nice to meet you sorry i dont have a gift bask- oh there it is!" *fel bombardment*. while there is a fleet hanging out nearby generally kicking the crap out of whatever non legion fleet/orbital defense platforms there may be.
fantasy micro, science fiction macro. should have never published Warcraft Chronicles with titan/void overall universe lore in them. or star ships for that matter.