The few rare offensive magics that would not be out ranged by 2500 feet would not be impeded by 12000 feet, and are very unlikely to be possessed by demons anyway.

He’s only encountered simulations of them in training exercise, but he really really hates Deimaviggas.

Nevertheless, we can try it, I believe it would not impede me.

Sending visual of target.

[A mental image of a spiky horned creature, that seems to be peering up nervously towards the sky, along with a kinesthetic sense of its location directly in front and below of her.]

It might take two (very rapid) shots to bring this one down; Tanya is still calibrating against different target types to avoid a repeat of the unfortunate incident in the square.

Up they go! Six thousand feet lets them see down all the streets of the city at once. Tanya obligingly manifests a magnifying lense in front of the appropriate shoulder.

What about nonmagical weapons? Guns, explosions propelling projectiles from a short tube, guided missiles or proximity fuses - optical sniping like I'm using - even without flight there's indirect-fire artillery, dragons could carry bombs, is anti-air fire really not used here? Or - the attackers didn't own anything sophisticated or couldn't bring in anything big by teleport?

...no, the attackers had no reason to bring AA if the city has no aerial defenses. Now she's embarrassed.

The lens works adequately.

Visual of target

[A mental image of a group of men lead by an emaciated red humanoid with a spear, along with a less focused image of the surrounding streets.]

Firearms and cannons are unreliable and inaccurate.  And very rare, outside a distant region where magic works less reliably.  This planet does not have nonmagical optical weapons.

Visual of target.

[A mental image of a winged horned woman crawling along the roof of a house.  A sense of the houses location in the city.]

Demons would have trouble procuring and managing the use of firearms even if they were more common on this planet.  Sustained long duration flight is 5th circle, Mendev, the nation this city is in, is poor in arcane casters and wizards in particular, and countering a few flying spellcasters wouldn’t be essential to the demons’ plan, insofar as they have one.  …my impression so far is that your magic has much higher limits on sustained usage.

Visual of target

[A mental image of a horned goat like humanoid committing arson, a sense of its location.]

Do you have any preferences among the exact mental formats I’ve used so far?  Kinesthetic sense vs. street intersection vs. city map vs. overall location?

Targets on streets: easy.

Targets on roofs: there's a risk of shooting through and hitting someone inside, so she tries to nudge the winged woman along with a meter-wide shot that should cause painful burns. The woman seems to have magical shielding against optical spells (?) or else a very alien lack of reaction to all her clothes being on fire, so Tanya puts an enchanted bullet through her head. (She really needs to conserve bullets...)

The goat is dead but Tanya has no way to stop the fire. No metaphorical bonus pay tonight, she has to do her job and trust that there are others who will do theirs.

Kinesthetic is fastest at letting me find the target. He's not giving her targets at the rate she could neutralize them (if she wasn't talking to him at the same time); hopefully after a while he'll trust her with more general designations instead of pointing them out one by one. ...It's not tactically crucial, even at this rate they'll soon pick off all the easy targets until the only bandits left are those with the sense to hide in buildings. Then they'll be down to the real work of urban warfare, either providing air support to ground forces or attacking mana signatures through roofs and walls and possibly killing hostages.

[He continues with a target and mental image every 3 seconds, consistently relying on kinesthetic senses.]

The target that required an alternate attack means was a succubus, one of the few demons that actually poses a threat to you if it gets a lucky teleport right on top of you plus a dominate.

They are already at a fast rate of a target every 3 seconds.  ...he's relying on instincts honed for more typical magic.

It occurs to me I fell back on training for this planet's spellcasting where a spell every 3 seconds is close the maximum.  If you can attack faster... If you recognize a demon type as one previously seen, feel free to attack without my targeting, leaning slightly more cautious if it looks more human, there is a non-demon species that can look somewhat similar to demons but more human, and leaning less cautious if the potential target is destroying property or attacking non-demon people.

That is probably more care than the city's defenders are showing towards tieflings, but he doesn't want to take any chances, especially if she's from Earth and is used to all humans.

A shot every 3 seconds? Without any enemy fire to dodge or aerial threats to keep track of? She'd fire a rookie for such incompetence!

Locating and verifying (and transmitting) targets is a legitimately hard task and she can't fault his rate, he's a civilian(?) contractor called in on short notice and has no access to mental acceleration spells. Tanya herself would have some trouble hitting widely separated targets if she had to shoot more than once per second. Luckily for her she isn't, technically, shooting.

The optical formula is meant for sniping targets in a close-range aerial dogfight. In theory the targets have no time to react, which means neither does the caster: once charged, the spell can be discharged at the speed of thought and in any direction. With her dual-core orb, Tanya can even cast several instances simultaneously. 

Of course, there is theory and there is practice. Good mages learn to track all the mana signatures in the sky, to notice the buildup of an optical spell (one with no significant buildup would be stopped by the target's barrier), to intuit its target and take evasive maneuvers, create decoys or an obscuring smoke cloud from an explosion, counterfire to force the enemy to move and disrupt their concentration, all while watching their wingman's back and coordinating with their squadron members to divide targets and keeping track of the broader battle and being ready to receive or issue orders or warnings at any moment. Mages who can't do this don't tend to survive their first few real dogfights; training, training and some more training is the mantra of the veteran professional.

Right now, practice is looking like a trainee's first simulated mission. Ground targets running about in confusion, complete freedom of the skies... Tanya is tense because of teleports (!!) and mind control (!!!!) but she is also tense because, on a subconscious level, things do not go this well and she is still waiting for the other shoe to drop. Even the Dacians at least tried to shoot her!

The Empire's military doctrine relies on agile, independent action by field officers in pursuit of the given objectives. Tanya has been as a matter of course mentally tagging similar-looking targets across the city; most of them lack mana signatures but she'd be a poor mage if she couldn't assault unsupported infantry out in the open. And she would have been remiss not to have a plan to take them all out quickly, ready to enact or present to her superiors as required. Even if this wasn't a job interview, hard work is a virtue.

She pushes her mental-enhancement spell all the way up and opens fire.

The next ninety-four seconds (sidereal) are very busy, and at the end well over three hundred targets lie dead. Also, Tanya has expended twelve more bullets and should really think about the logistics of local procurement.

On the downside, a few targets survived her first shots and managed to teleport away because she still hasn't fully calibrated the necessary power and she can't exactly overpower every single one of them when casting this quickly.

That was extremely impressive!  Also, as he’s gotten more oriented and there is now a momentary shortage of targets, he’ll ask another question seeing the teleports has prompted.

Has the Wardstone been disabled somehow?

Terendelev has barely paid attention to the telepathic bond (but she has realized Tanya is even more ridiculously powerful than she thought), but she has a moment to respond.

It seems it is entirely nonfunctional.  There is some form of corruption that was hidden by a very powerful and subtle illusion.  It must have somehow been covertly corrupted before the attack.  I’m organizing a defense of it to prevent further corruption - I’m worried with further access the demons might have someway of affecting the adjacent wardstones or even the entire network - Inheritor forbid it!

So the 'demons' infiltrated the city (by more ordinary means), sabotaged the Wardstone, carefully hid the sabotage from routine inspection, and then took the time to coordinate an attack by teleport? Whoever pulled this off is a serious threat, not just an opportunistic bandit. Perhaps an enemy state, or a very competent criminal organization?

She doesn't expect her input to be valuable here, she's missing too much context. For now she's content to neutralize targets as directed.

Even as disorganized and distracted by their revilement in the chaos as they are, the demons eventually start to notice the transient beams of light from the sky that keep killing them.  The responses are haphazard.  Many demons simply hide, a few dart from house to house quickly, seemingly hoping minimizing their time outside will be enough to let them avoid being slain.

Jon focuses more of his target identification on humans as Tanya seems to have identifying demons handled.

The city's defenders rally at the Cathedral Tanya was at earlier, as well as around the rift in the earth above the Wardstone, where they eventually get rope ladders setup.

New demon occasionally teleport into the city, and the existing demons seem to have no better plan to learn if there is still a threat than poking their heads out, so Tanya will still have occasional targets even a hour or so later.

Just checking in, this telepathic bond will only have another 20 minutes or so.  We've continued to hold the Wardstone, barely any demons have attempted to attack us.  If you still have magic left... how powerful can you make your searing light?  Do you have any way of moderating collateral damage?  The Grey Garrison [Mental image of a fortress Tanya should be able to recognize] seems to have been taken by a major concentration of demons, although I'll get more confirmation before I ask you to outright destroy it.

Tanya can detect magic being cast from within the fortress, although if she hasn't learned to discern different types of spells yet it will be hard to guess if it is active combat or anything else.  Not many demons have appeared exiting or entering the fortress, so they must have had another way in.  Directly teleporting?  Some underground passage?

I can straightforwardly make the spell about three times more powerful than my first attack against the - enemy that tried to cut off your head. Which was much more than the strongest attack I've had to use since then, she clarifies for Jon's benefit. More than that is possible but - complicated. To collapse a building it would be much more efficient to use explosive shots but I have a limited supply of bullets. We have not discussed yet how easy it would be to manufacture more or the infosec implications. 

I can only mitigate the damage by aiming and by modulating the power. If I try to destroy the building in an instant it might set the surrounding buildings on fire and send chunks of stone flying out at high velocities, and I still couldn't guarantee that those inside won't manage to teleport out.

Do you mean to destroy the building instantly and kill them before they can teleport, or is it acceptable to drive them out more slowly than that and risk them occupying another building? There are mana signatures inside the building and I can target those without destroying it. If you can provide building plans including the support columns and wall thickness that would also help.

What enemy would be strong enough to outright cut off an elder Silver Dragon's head?  Did Khorramzadeh attack earlier only for Tanya to drive him off?

[Over a whispered message just to Tanya]  "I didn't have time to explain earlier, this planet lacks industrial manufacturing, especially anything high precision, so you'd be reliant on specialist artisanal magic-based manufacturing techniques to replace your bullets.  Also if anyone manages to reverse engineer them, the long term implications are... complex."

Over the telepathic bond:

The demons will lack the morale or organization to regroup anytime soon if they scatter, so the slow destruction of the building minimizing collateral damage may be worth it, unless there is a particularly high value demon to kill inside?  All the teleporting demons will now have locations memorized inside the fortress, so you would want to do substantial remodeling anyway, even once the Wardstone is functional again.

He really hopes they can get the Wardstone functional.  He's not volunteering to go inside a new one!

I can send you mental images of the fortress while our bond is still up.  I'll start sending them in a moment... Jon you have the better than human memory to hold onto them, right?  As for bullets, there is a 1st circle spell that can from a single arrow or bolt or sling bullet make a container have an endless supply of them for a matter of minutes per caster circle, although the ammunition is only temporary and disappear when the spell ends.  I could try to find a scroll, but my next priority is confirming that we've lost the Garrison.  Once I've confirmed, driving them out more slowly is acceptable.  If you can kill them even through the walls at range, that would also work... if you can tell the strength of the target, prioritizing the strongest demons would make sense.

Tanya continues to be absurd!  If Terendelev followed correctly, she can somehow detect magic at immense ranges through stone walls?

I have near eidetic memory and should be able to hold detailed plans of the building mentally at the ready for Tanya to use.  Stronger demons usually have stronger magic and I agree it would make sense to target them first if possible.

To Tanya over the message: "If the explosive charge is packaged with the bullet, depending on the exact chemicals used and details of the exact design, the standard version of the spell she mentioned, Abundant Ammunition, may not work correctly.  Even if not... if your bullets are manufactured with industrial precision, the spell may have minor trouble with quality.  If your bullets are enchanted, the spell will also not work correctly for that reason."

He really hopes Tanya has at least heard of those concepts before, otherwise that sentence alone will prove to be costly (even if the leading edge of experimentation in Alkenstar has technically made the relevant discoveries already).  He is in fact really sure from what he's seen (and smelt, and inferred from communicating with her so far), but he is acutely aware of the risk, however small, and accounting for it.

I'll try to have confirmation before this telepathic bond ends, I'm working on obtaining another scroll but it is unlikely I can find one.

She proceeds to send lots of high quality pieces of a mental map of the building. Her memory and spatial cognition is a bit better than a smart wizard with an excellent headband, so the mental map is quite precise and detailed and well organized.

"The bullets are cartridges that include the explosive, machined with an etched pattern that allows them to be quickly enchanted when they're fired. We don't have stably enchanted items," she reminds him. 

The planet doesn't have industrial manufacturing and he's not sure about cartridges? Jon recognized the concept of firearms, so Tanya assumed whatever was wrong was local to this city! What are these people used to, powder horns?!

The fighting was chaotic at first, people grabbing the swords and longbows they had - prepared for the local festival - and the attackers were bandits and swords don't need reliable supply chains - if you can teleport straight into melee guns do lose a lot of their advantages - but enchanted guns should still be better than enchanted longbows and no trained army or militia or police force with real weapons has turned up and people are still dying down there -

Did they build an interstellar, multi-species civilization using teleports alone (well, that and mind-control) and never got around to making any technological progress? Did they never invent the concepts of science and engineering, is that why they're so obsessed with religion?

...No, Jon said 'this planet' and he was called from... somewhere... did Tanya end up in a backwater colonized by technologically advanced planets? If teleports are rare and expensive there wouldn't be much trade in material wealth, and if the colonizers aren't interested in the land (perhaps they're all different species?) then it might be less of a colonial situation and more of a rich neighbor uninterested in anything this place has to offer. Anyone who's smart and capable enough to learn to teleport to other planets or to pay for it leaves, leaving behind this mess of anarchic 'demons' surrounding primitive walled cities protected by wardstones they cannot easily repair or replace. Ricardo's law is all very well but it can't stop a perpetual brain and wealth drain.

That is a terrible situation to be in! Like every rational person, Tanya wants to leave for the true civilization that might be waiting for her among the stars! But she'll need to gain some local wealth first, and learn more from Jon once the fight is over.

Terendelev's imagery shows the building has a large internal open space spanning its entire height. 

I can collapse individual rooms easily, or snipe at mana signatures in them. If I fire at the roof's middle it should easily penetrate to the ground level but it wouldn't kill everyone behind the internal walls; the explosion would probably blow the rest of the roof off and most of its force would escape upwards.

If there is an especially powerful or notable demon it might be more worth killing them than maximizing the number of demons killed, in larger scale battle demons are notoriously dependent on individually powerful demons capable of leading and driving them.

I’ll ask if anyone has identified a leader at the same time I get confirmation.

In the city below, Tanya can see Terendelev crawl out of the crack in the ground and fly over to the Cathderal.  About 15 minutes later…

I have confirmed the Garrison has completely fallen to the demons, we will withdraw our soldiers from around it within the next ten minutes.  This telepathic bond only has 5 minutes left, so you have the go ahead without further instructions from me after ten minutes.  The demons have a leader, a Lilitu witch, Minagho.

[Mental image of an eyeless humanoid demon wearing a stylish red dress.  Mental imagery of guesses of some of the locations within the Garrison she might be likely to be.]

If you can identify the strongest demons or the strongest spellcaster to kill that would likely be her and should be a priority.  You may delay attacking within the Garrison up to half an hour to try to identify this target.  Otherwise, picking off any and all magic you can detect within is my best guess at how to attack, although I still don’t understand the exact limits of your magic.

Every army depends on its field leadership and on its strongest fires and mages. Is Terendelev implying that her own people would fight on well if she were dead? Indeed, morale is a crucial factor, and the enemy's morale seems very high considering they haven't fled the city yet. A soldier fleeing mid-battle has to run past his fellows and into his own rear ranks where he'll be shot for his trouble; a soldier who can just teleport a hundred miles away will presumably do so much more readily in the interests of personal survival. Perhaps the organizers of this attack recruited the bravest suicidal warmongers who'd rather fight to the death than flee, or perhaps they're holding their families hostage...? But then, why would killing their leaders help?

Well, she can't be expected to understand alien barbarians. It's probably something she'll need to have explained to her. For now, she has her mission parameters.

I can detect approximate power, location and movement, identify previously seen signatures and spells, but I don't get visuals.

Plan is to wait ten minutes; afterwards, if an unusually strong mana signature appears or if we spot the target, attack immediately; after half an hour without action, begin attack in order of mana signature strength, then any demons visibly leaving the building, then collapse it while avoiding collateral damage. CP, please confirm, she almost says.

If you eliminate over two dozen targets within or fleeing the building, hold off on outright collapsing the building, I believe it will be worth fighting to reclaim it.  If less than that, then yes, also collapse the building. 

8 minutes later, from within the Garrison, Tanya can detect powerful spellcasting, stronger than any spellcasting she has detected so far save Terendelev and the giant demonic-construct from earlier.