Ow, ow, ow. A number of people nearby do have some level of combat certifications, but when dath ilani drill those skills it's typically self-defense-only or group-safe-subdual courses and neither are predicated around fighting an organized group with weapons while unarmed; the usual advice there is "don't." There are more calls going through to emergency services now, because even without new pertinent details each reporter can still move their internal prediction market about whether this is actually happening, and more bystanders are going to join in on recording. That doesn't seem to be provoking a reaction from whatever this group is, at least, and if you predictably refrain from recording events because other people seem to have it covered then it'll turn out tomorrow that the only people with recording were working with whatever group pulled off the stunt and none of the footage shows anything they didn't want it to.

Elsewhere in Schelling Point:

In another circumstance, Mylonas would perhaps be willing to admit there was a certain humor in the situation. There were no shortage of ways a city's defenders could make the lives of cavalry hell, and some part of him had been dreading an encounter with foreign magics or battlements of archers or tight ranks of heavy infantry ever since he first learned of his role in the Legate's plan, but never had he expected that the largest roadblock in his efforts would be the vagaries of foreign architecture of all things. If you'd mentioned it to him yesterday, it would never have come to mind as an issue! After the third false start, however, he was forced to face facts - he had absolutely no idea where to even find the local administration. To his untrained eye every building in the city was practically the same, and his efforts to search those that stood out from the pack had thus far turned up a library, an indoor market, and what was presumably some sort of barbarian ritual space he didn't remotely have the context to recognize.

The locals weren't any help  - he and his men could scare them, no problem, but not one among them would admit to knowing a civilized language no matter the pressure. He'd have thought "take me to your leader" wouldn't be hard to grasp from a group of invading soldiers, but they weren't terribly smart either, and even killing a few of them didn't get the rest to wise up. Perhaps a scholar or soothsayer could get something out of the resulting babbling, particularly given the common threads therein, but 'see imbeye' was so much gobbledygook to his ears and the more comprehensible screaming didn't exactly give him new information. The only real positive of the affair was the lack of resistance - if the city did have a standing garrison, it was either well away from the downtown area or asleep at the reins, and both cases meant they could rest relatively easy when it came to retaliation. There would be time to join in on looting the place, at least once they'd done enough searching that they could defend their failure to capture the local magnates.

Schelling Point emergency services is aware of the problem. It would be an exaggeration to say they understand the situation, but they have a lot more to go on than most of the people on the ground; there are quite literally hundreds of people around the city relaying their observations to the authorities, and they've supplemented this with an emergency protocals that give them access to (almost) all the cameras in the city. Within two minutes of the mysterious building first appearing, the situation was emergency services' top priority; within five, they had already escalated it to exception handling and started roping in keepers. 

The fundemental problem about dealing with it is that it's impossible. Forget the thing it's presenting as being, which is ludicrous on its face; how you'd go about convincingly faking the evidence they're getting is still unclear even having seen it done. They've already done the tests to rule out the worlds where it's an disciplined conspiracy of supercriminals with one good trick; you've got to posit an enormous group of supercriminals of unprecedented organization that also have multiple undiscovered tricks, and even once you posit that being true it doesn't really make them any less confused about what's going on. They're not all keepers, but even the average dath ilani is good enough at cognitive self-reflection to notice the problems there. And while it's typically considered best practices with confusing situations to make small, careful changes to iterate your model until it starts cohering, the 20th percentile guess is that true lives are at stake and the upper plausible limit on the number is alarmingly high.

So you're paralyzed with indecision?

No, of course not. Even children are capable of figuring out that not deciding on a course of action is usually one of the worst possible ones in a crisis, and emergency services is exceedingly well drilled at avoiding that particular pitfall. What they're explaining is why governance is not currently scrambling an airstrike.

By the standards of its technological contemporaries, dath ilan's military is one of the least impressive parts of their civilization. They possess few grand fortresses, can speak of no great glories won in battle, and do not march in grand ranks. Across the entire world, and even including those civilian positions necessary for keeping the machine flowing within their numbers, less than a tenth of a percent of dath ilani are employed by the military at any given time, and even those slated for combat roles have often rather anemic ordinances.

Much of the reason for that is from a lack of need, but that's not the entire story. Certainly dath ilani have all been under one government for longer than recorded history*, so its deployments and procurement need only consider responding to infrequent internal threats, but even those strictly limited and knowable threats could justify a larger force. It's not even a question of money, either; certainly civilization would prefer not to spend resources inefficiently, but the rates at which they will trade their enormous wealth for preserving lives - even stochiastically, for most would not consider it a critical distinction - would stagger belief. Instead the reasoning is rather more structural, in that dath ilan does not in fact want its government to have a monopoly on force. Certainly all else equal they would prefer the armed forces capable of dealing with emergencies, but not at the cost of enabling it to stay in power without the support of the population at large, and the role a hostile military could play there is obvious even to people who phone in their efforts when it comes time to practice overthrowing the government. And since a key part of keeping those counterfactuals strictly counterfactual is ensuring nobody is incentivized to try it, there are an enormous number of checks on the army to limit what it can do, and especially what it can do in a hurry on governmental orders based on fantastical information.

One of the key consequences of this is that it's not exactly trivial to bomb one of their own cities** even if they wanted to. They could manage it once, if everyone involved in the decision making were to have themselves imprisoned pending trial to accomplish it, but - even if everything were exactly as it bafflingly seems, the difference between handling this alien attack optimally or not is conservatively thousands of lives. (There's also some significant concern about whether it would even work out that way - spears and arrows are not a particularly terrifying armament, but an army best modeled by that capability wouldn't appear without warning from a space that absolutely could not fit them with no prior records of their existence).

*A significantly less impressive timespan than it might sound, though the planet has indeed been unified for a while.

**With one notable exception, but it's the thorough hope of everyone involved that that particular contingency will never be needed.

And so for now the missiles remain unfired, even if not all the planes that could launch them are still on the ground, and a similar forbearance goes for most of their other indiscriminate weaponry. This leaves emergency services with the unenviable problem of time. Civilization does technically have plans for dealing with an alien invasion, but the assumption has always been that by and large such an event was unlikely to occur and beyond their ability to win if it did. Between dath ilan and a civilization already capable of crossing the stars... there's only so much you can do at the other end of a power gap that large, even before you consider the fact that any opponent not confident in their ability to win such a fight could trivially avoid picking it. They're putting together new plans almost as fast as the new information flows in, but they're new plans, and the difficulty of logistics in haste is as always a problem. Everything more complicated than evacuating the city is going to take longer than anyone involved would like.

And in the mean time-

Yeah. People are going to die. 

Just be glad this isn't one of the legions that likes to take skulls as trophies.

...They had not been tracking that as one of the ways this could have been worse. Why would anyone do that?

Tribune Benatus is not, exactly, satisfied with the status of the gate fortifications. It's not that they're bad work, by any means, though he's confident he could have done significantly better if they weren't racing against time - having a ready stockpile of construction materials goes a long way. The problem is the blasted city. Whatever bizarre local concrete they use to pave the streets is the next best thing to impossible to dig through without magical tools, and for some Hardy-damned reason they put it everywhere, limiting how much he'd trust the walls against any siege equipment. He doesn't trust the local buildings they've taken over as hardpoints either, not with how difficult the bigger ones are to properly sweep and the risk of an aerial insertion. It'd be better if they could just block off the staircases, but then anyone who could get there would have free reign to start raining down arrows or pitch or whatever improvised ammunition came to mind down on his people's heads, so he just has to live with the uncomfortably large troop detachments they require.

Still, perfect is the enemy of good, and unless his men missed an invisible mage there's nothing in position to threaten the gate right now. He gives the order to let the dragon riders off their leash, and the steady stream of soldiers and materials into his base camp parts to allow the enormous beasts room.

Finally.

Wait, no, back up a second here. Are those wings?

Yes? How else would they fly, hydrogen sacks?

It's not that it's inconceivable, so much as... flying creatures exist under a handful of very tight constraints, and large animals capable of powered flight don't look like that. Dath ilan has fossil evidence of a handful of species in roughly the right ballpark of size, and they all shared key traits by necessity.

Firstly, they need to have large enough wings for their size and a sufficiently aerodynamic body to have enough lift to stay aloft. Something around fifteen to one in lift per drag, in the ideal case, but certainly not less than five. Secondly, they need to be light. Every kilogram of mass in their body is another 10 newtons their muscles need to offset whenever they want to gain height, and flapping your wings is not the most efficient way to supply thrust imaginable. And thirdly, particularly if they do a lot of taking off from ground level, they need enormously powerful wing muscles. These “wyverns” fail all three, even before you consider the fact that they're carrying a rider (!) wearing heavy metal armor (!!) into battle. And you can't just say that it's genetic engineering, either; a modern sailplane can be enormously more efficient than any bird at flight, but the way it does that is by having a very precisely engineered shape, which again does not look like a wyvern.

That's a bit of an exaggeration. They do make heavy concessions to the rider's weight; much like a horse jockey, the ideal imperial dragon rider is short and slender, and their kit is stripped down as close to the bone as possible. Their armor is made of bespoke plate, ruthlessly optimized to only cover what it must and enchanted for strength so it can be hammered thin without compromising the defense. Their saddle is simple and unornamented, sufficient to allow them to stand in their stirrups and prevent the wyvern's scales from chafing against their clothes, and little more. And the weaponry - oh, there the compromises run tight and dear, much to the dismay of every enterprising legate with the idea of dropping rocks or tar or flaming oil on their foes. This also gives insufficient credit to the muscles the wyverns do have, and the powerful metabolism that fuels them - a wyvern can easily eat an unsuspecting noble family out of house and home.

And?

And they're the chosen of the sun god Flare, though he rarely bestows his direct favor on any save for true dragons. If you think these are bad, you're in for a rude awakening later.

...Noted.

By now the surroundings of the gate are clear enough that no actual dath ilani eyes see the arrival of the dragons, but while a number of cameras were smashed this was mostly incidental. It's not immediately certain to the watchers that this is an air force, both because they know enough aerophysics to doubt the wyvern's capabilities and because dath ilan wholly lacks the concept of dragons as a specific alternatephysics animal, but they can see the wings and pull back the two stealth observation drones they've managed to scramble accordingly. The numbers are quite concerning; none of their pilots like the idea of engaging a foe of unknown capabilities, and they'd be doing it at a numerical disadvantage until reinforcements finish re-basing and refueling at local airfields. Additional anti-aircraft weaponry is distributed to the mustering infantry, and the evacuation advisory increases its urgency and starts prioritizing getting people too close to leave the city in time into shelter.

It's a little late on that score. Wyverns are, when they feel the need to be, extremely fast. Not by the standards of a fighter jet, certainly, but dogfighting a vtol aircraft isn't impossible as long as it doesn't turn into a race. Once they get oriented they can cross even a city the size of Schelling Point in a matter of minutes, and unlike the cavalry their aerial view is a huge advantage in identifying clusters of people, and in particular which if any are plausible candidates for military organization.

Like, say, emergency services detachments helping coordinate the evacuation.

It was always likely that they would prove unable to actually avoid a conflict entirely here, not when the aliens have been acting uniformly hostile to everyone they meet and proven extremely difficult to communicate with. They would still really like to avoid it, but not so much that they're willing to sacrifice this many people to delay it by a bit. 

The soldiers deployed around their approach open fire.