Last Stand at Shanxi (Mass Effect AU)

[ryune]

Hmm, can we get an Asari perspective? Maybe one of the ones that negotiated the ceasefire?

 

[Slayer Anderson]

I like this. Definitely watched.

I'd enjoy seeing an asari perspective as well. Either one of the peacemakers or Tevos herself dealing with the ongoing problems of a non-Citadel humanity and silently seething over the turian councilor.

 

[Doghead13]

Conveniently, I'd already roughed this out when you gents posted your requests for an Asari POV. It took a bit of bashing into actual shape, but anyway,

-/-/-/-/-/-

The Turian attack on Shanxi was the beginning of the end, and our response - my response - at the end of the day succeeded only in insuring that the end would, indeed, come.

It was in hindsight an unreasonably beautiful day when I learned that something unreasonably big and unreasonably bad was happening on the edge of the Attican Traverse - two relay jumps from Illum of all places, in the system containing the then-dormant Relay 314: the specific information handed to me was that somewhere in excess of three thousand Turian soldiers had been shipped back to Heirarchy space in body bags over the span of a little over three months - whatever they'd run into was killing them faster than anything we'd seen since the Krogan rebellion.

It should not come as any sort of surprise to anyone that I got moving immediately, and didn't skimp on the backup. A matron of my age and influence can call on a statistically significant portion of the Asari navy, and that is exactly what I did.

What I found was absolutely horrific and raised serious questions about the Turian suitability to remain the mainstay of military force in Council space, I know exactly what they thought they were doing and it wasn't 'enforcing council law', influential the Citadel may have been but they were not fool enough to think their laws extended to species who've never heard of them. There were nearly a dozen treaties needing signed before so much as one paragraph of interstellar law applies to a species and the Turians were and remain perfectly aware of that: what we all know they thought they were doing was snatching up the new kids on the block to make a useful client species of them, with that relay acting as a politically convenient excuse.

Getting the Turians to stop shooting took very direct throwing my weight around: to cut a long story short I was forced to declare that if the Turians didn't agree to an unconditional ceasefire immediately the Asari Republic would be forced to jump into the war on the newcomers' side - a declaration that I made in the full knowledge that it was endangering one of the key treaties on which the Citadel Council, and ultimately interstellar law, depends. I must confess that the idea that the newcomers would refuse to join the Council, thus causing the actual collapse of that treaty, never even occurred to me.

As a direct result I became the first non-human sapient to set foot on Shanxi post the Turian withdrawal, and even today I struggle to find the words to convey what I saw there.

The humans were burying their dead, of whom there were so many, so many, that they'd had to bring in a small army of construction workers and they still expected the job to take them months. There are now fields stretching for kilometers covered in identical little cross-shaped concrete markers, each painted white - and those are just the bodies they have been able to locate: a majority of their dead have no grave site, no known place where their body lies, and a great many did not leave any meaningful body at all.

The condition of the survivors - what few of them there were - was appalling. I saw one, a child who given their lifespan can't have been more than a few years old, little more than a baby, asleep jammed tightly into a corner with a battered, heavily-used, primitive firearm clutched for dear life in her hands. Each one of them was little more than skin and bones - I later learned that they had been forced to resort to cannibalism to survive, I could happily have murdered the Turian politicians and officers responsible for the decision to continue their war until that point by the time that I returned to my ship.

The following weeks were riddled with further failures. The Humans were, in all honesty understandably, not in the mood to make nice. They discarded the possibility of joining the Council out of hand, nor were they even momentarily willing to sign any actual peace treaty with the Turian Hierarchy - their lead negotiator privately told me that the idea was politically untenable in Human space, and that a popular lobby was calling for an escalation of the war. I was shown plans they had already drawn up for a black marble wall bearing a little over two million names, each and every one of which they described as a pressing argument against any such peace treaty.

The resolve of the Human diplomats was as one, backed up by their press and public opinion; for so long as the Turian officers and politicians responsible for the war still draw breath, there can be no peace. That responsibility lays at the very highest levels of the Turian power structure: the decision to invade, and to continue the war post its turning into a meatgrinder, involved their head of state.

(Relay 314 was opened fifteen days into the ceasefire, One of the Human diplomats admitted to me that it had become essentially politically impossible not to activate it. Thankfully, no Rachni-like threat lurked beyond it; I do not believe that the Humans have opened any further dormant relays at this time, though at the end of the day we do not actually know.)

In many ways as a result both of my failures and of the Turian's actions, the galaxy is a considerably more dangerous place now than it was then. The Turian-Human Cold War has as of today lasted fifteen years. The Humans and Turians have continuously engaged in brinkmanship, sabre-rattling, and clandestine operation against each other, the Batarians insistently continue their incredibly provocative actions against the Humans - not without injury on the Batarian side, mind, the Humans take great satisfaction in carrying through their assurances about the throwing of slavers out of airlocks and there are more than a few members of my species who owe their freedom to the Systems Alliance Navy - half a dozen assorted treaties have collapsed - largely as a direct result of my threat to bring the Asari into the war on the Human side - and the Council itself is facing total disintegration, the collapse of the mutual military support treaty caused by my failure to bring the Humans into that same treaty has seen to that; whether there will be a Citadel Council in just a few years time I could not say.

If circumstances between Human and Batarian do not deteriorate to the point of all-out war, the cold war between Turian and Human is going to go hot, and it is going to do so very soon. All it would take is the right flashpoint to begin the war that all three have spent the last fifteen years preparing for - and I can't help but fear that it will spark an inferno that will consume us all.

The lights are going out all over this galaxy, and we will not see them relit in our time.

 

[Gromweld]

While this would ostensibly mean the Reaper Invasion would basically be a walk in the park for the mecha-cuttlefish if the timeline stayed the same, an amusing thought is that Sovereign would actually wait to start Reaper invasion; the stated goal of the Reapers is to let organics flourish and reach a reasonable level of general unity/stability before starting the Cycle. Which... would mean that they'd want to wait a bit longer for things to settle down and the Galaxy to fully unify again. But then Shepard isn't around, and so the Reapers still win? Shrug.

The events of the Mass Effect series are generally implied to be a 'best it's ever gonna get' situation for the fight against the Reapers, and even then - with the entire Galaxy united in one massive fleet - the Reapers still win if the player doesn't choose one of the Red/Blue/Green endings. Changing even a little to make things worse... yeah, incoming Bad Times Ahead.

 

[Slayer Anderson]

The lights are going out all over this galaxy, and we will not see them relit in our time.

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Ah, good to see a man of culture on QQ. Very nice quote, especially for the setup.

 

[SlickRCBD]

While this would ostensibly mean the Reaper Invasion would basically be a walk in the park for the mecha-cuttlefish if the timeline stayed the same, an amusing thought is that Sovereign would actually wait to start Reaper invasion; the stated goal of the Reapers is to let organics flourish and reach a reasonable level of general unity/stability before starting the Cycle. Which... would mean that they'd want to wait a bit longer for things to settle down and the Galaxy to fully unify again. But then Shepard isn't around, and so the Reapers still win? Shrug.

The events of the Mass Effect series are generally implied to be a 'best it's ever gonna get' situation for the fight against the Reapers, and even then - with the entire Galaxy united in one massive fleet - the Reapers still win if the player doesn't choose one of the Red/Blue/Green endings. Changing even a little to make things worse... yeah, incoming Bad Times Ahead.

Click to shrink...

Well, you could say that the United States was far stronger militarily at the end of WWII than at the start, as were most of the Allies. Even the Soviet Union had started rebuilding and was at least as strong when the Germans surrendered as they had been in 1941 despite their country being ravaged by the scorched earth tactics (although that was primarily by mustering their forces and through lend-lease providing equipment, it took them years to rebuild their industry). On the other hand the Axis were in shambles.

A galactic wide war might spur technological development that is exactly what was needed to fight the reapers. The militaries of 1945 would wipe the floor with the militaries of 1938 (or even 1941) due to far better technology and equipment.

Remember also that there were restrictions on fleet size similar to the post-WWI Washington and later London Navy Treaties and this war would almost certainly remove those treaties from effect. It might mean that in the end there is actually a larger fleet to oppose the reapers as a result of that.

I'm merely drawing parallels to real world examples.

 

[mattsaber]

While this would ostensibly mean the Reaper Invasion would basically be a walk in the park for the mecha-cuttlefish if the timeline stayed the same, an amusing thought is that Sovereign would actually wait to start Reaper invasion; the stated goal of the Reapers is to let organics flourish and reach a reasonable level of general unity/stability before starting the Cycle. Which... would mean that they'd want to wait a bit longer for things to settle down and the Galaxy to fully unify again. But then Shepard isn't around, and so the Reapers still win? Shrug.

The events of the Mass Effect series are generally implied to be a 'best it's ever gonna get' situation for the fight against the Reapers, and even then - with the entire Galaxy united in one massive fleet - the Reapers still win if the player doesn't choose one of the Red/Blue/Green endings. Changing even a little to make things worse... yeah, incoming Bad Times Ahead.

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not necessary, they would invade one way or another. they could decide to wait and let them destroy themselves or invade while they are at war. either way the galaxy would not be united and be easy pickings.

 

[Doghead13]

The events of the Mass Effect series are generally implied to be a 'best it's ever gonna get' situation for the fight against the Reapers, and even then - with the entire Galaxy united in one massive fleet - the Reapers still win if the player doesn't choose one of the Red/Blue/Green endings. Changing even a little to make things worse... yeah, incoming Bad Times Ahead.

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See, I don't buy that.

The entire Mass Effect series has the galaxy hilariously lightly-armed (I wouldn't call any of the canon fleet sizes enough military assets to adequately cover one star system, never mind thousands) due to operating under pre-WW2 style military treaties, riding high after several millennia on a peacetime footing, and essentially technologically stagnant. It can very readily be read as having been done by design, there's already a vector to do so via - indoctrination - and a vessel through which to indoctrinate everything and the kitchen sink; the Citadel itself.

It can be read - and this fic assumes as I strongly dislike apocalyptic endings and not to put too fine a point on it found the canon ending of Mass Effect eye-rollingly bad - that the Reapers use the Citadel to make the biologicals defeat themselves via stagnation, complacency, disarmament, and the installation of a comically blinkered government prone to 'dismissing these claims'.

The result of an utterly runaway cold-war arms race is a very, very different animal indeed. Quite a lot darker, quite a lot more violent, but VASTLY more heavily armed. By the time of the planned segment about the flashpoint our unnamed Asari Matron fears there are more, and more advanced, dreadnought-class warships in any one of the eight squadrons making up the Sol Home Fleet - effectively the human home defence force - than there were in the entire canon Mass Effect galaxy. The entire combined militaries of every canon Mass Effect race put together would be insufficient to make up one squadron of one fleet of any major player's navy - and the most advanced warship in Mass Effect canon would be considered hopelessly obsolete.

Ah, good to see a man of culture on QQ. Very nice quote, especially for the setup.

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Seemed too perfect a fit not to use it, aye.

 

[Sidvious]

snip

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This. I assume they either left shanxi totally uninhabited as a monument, or far more likely turned into such an ludicrously armed fortress that Cadians would be envious of how well defended it is.

 

[Doghead13]

This. I assume they either left shanxi totally uninhabited as a monument, or far more likely turned into such an ludicrously armed fortress that Cadians would be envious of how well defended it is.

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Somewhere in between.

By the early 2170s - the timeframe all the existing segments are set in - Shanxi is a major naval base amounting to a fortified strong point on the frontier of human space, and the site of the General Graham D Williams Memorial Station orbital shipyard complex - one of the Systems Alliance's seven facilities suitable for the erection of capital-class warships. These yards run full tilt, night and day - a completed battleship is signed over to the navy every ten days, with smaller vehicles leaving on the hour, every hour, and usually as many as six to eight thousand vehicles under refit at any given time. During times of war, it would be the front-line repair yards for any thrust into Turian space.

The planet itself has been recolonised. The site of the old colony's capital city is now considered an Alliance war grave - there are roughly one point two million unaccounted-for human bodies somewhere in the rubble - and as such is patrolled night and day by dress-uniformed Systems Alliance soldiers in a manner directly and deliberately analogous to the Tomb of the Unknown Soldier. It does, however, retain seventeen living residents: the adult survivors of the war all flat-out refused to leave, and all remain resident in the city, along with the families three of them have began since the war - one as a couple who met via surviving the war together, the other a woman who married a Systems Alliance Marine who then joined her as a resident in the place now known as the City of the Dead.

The new colony is on the same continent, but a couple of hundred miles to the north, directly next to where the Turians first set foot on the planet and grown up out of the camp that was set up for the temporary population of construction workers in the aftermath of the war; the location of the Turian basecamp is now a sewage works, and an open-air settlement pond stands where the Turian headquarters was once set up, very deliberately of course. The new colony was, while still a transient camp, named Douala by the leader of the team that broke ground in the building of it, after his hometown in Cameroon on Earth. He is now a resident, and has been joined by numerous fellow Cameroonians - the planet now hosts the largest concentration of persons born in Cameroon off of Earth.

As of the 2172 census Shanxi has a civilian population of a touch over twenty-six million, with a very high percentage of them naval shipwrights and support staff. The colony is quite ethnically diverse; that said there are over three and a half million ethnic Bantu and nearly three million each of ethnic Cambodians and ethnic Scandanavians on the planet, which has began to establish an interesting hybrid culture of its own.

There is a small but famed non-human minority on Shanxi; this group is made up of ex-slaves freed by personnel from the fleet elements who call the planet their home port. Nearly half a million non-humans now call Shanxi home, some ninety-five percent of them slave-caste Batarians, and the first Batarian officer was recruited into the Shanxi Colonial Police Department in April of 2170. Incidentally, this makes Shanxi the planet with the largest non-human population in Systems Alliance space. None of them are Turian, nor have any of the twenty-six Turians to legally enter Systems Alliance space since the war ever been granted permission to set foot upon Shanxi, and Turian civilian vessels are advised not to approach within several AU of Shanxi as they are liable to be shot down without warning - this has happened on four occasions.

The planet has a comprehensive gun culture; this can be considered typical for all modern human colonies post the invasion of Shanxi. Nearly ninety percent of adults on Shanxi own at least one firearm, local gun laws are extremely permissive with many military-grade weapons considered civvy-legal, 'invasion preppers' are very common, and over a third of the planet's adult population are members of the Shanxi Territorial Army Division. Violent crime is very low, however those crimes that do occur (some ninety percent of which can be classed as crimes of passion) inevitably result in gunshot injuries - as a result the murder rate is downright painful. The local police are easily as heavily armed and armoured as the Systems Alliance Marine Corps; they need to be.

In addition to the Territorials a division-scale professional military ground forces presence is maintained onworld at all times, stationed at Camp Graham roughly halfway between the old and new cities - at any given time two companies, one armour and the other motor infantry, will be stationed guarding the City of the Dead. Soldiers are never required to spend more than six weeks stationed at the City of the Dead as it's renowned for seriously impacting morale in units kept there much longer than that - there aren't many soldiers come back from duty there without believing in ghosts. During times of war, this presence would most likely be swelled to four to six full-scale army groups.

In space, representing the lion's share of the system's military presence, Shanxi Station is typically guarded by the First Attican Sector Fleet, Systems Alliance Navy, formed from six full-strength squadrons any one of which would be a match for the combined navies of the entirety of Mass Effect canon. At any given time two of these squadrons will be in orbit of the planet with the remaining four on patrol in the surrounding systems, chasing Batarian 'pirates', or rattling sabres at the Turians across the border. In addition the system is full of thousands upon thousands of manned defence platforms, each able to provide firepower equivalent to a cruiser - all in, out of the dozen most fortified systems in Human space, Shanxi is at place number seven.

It would be a tough nut to crack.

Edit: At the suggestion of Slayer Anderson, have threadmarked this post.

 

[Teiwaz]

Hmmmm....
Needs more.
Shanxi needs to become a Terranis.
Terranis will hold. Always.

 

[Slayer Anderson]

Somewhere in between.

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You should probably threadmark this, given that it's over 1K and contains a lot of good info.

Maybe 'Shanxi of the 2170s' or 'Shanxi Today' or something like that?

 

[Akshka]

all in, out of the dozen most fortified systems in Human space, Shanxi is at place number seven.

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fucking seventh...... I have not read about anything this heavily fortified that was not in Warhammer

 

[Sidvious]

Pretty much exactly what i was imagining tbh. I can picture the reapers using the empty city as a staging area when they (eventually, and not without loss) touch ground. This does not have the intended effect of breaking morale, and backfires. Severely.

EDIT: Ashley's family instead of being military pariahs must be goddamn saints in the flesh

 

[SlickRCBD]

Hmmmm....
Needs more.
Shanxi needs to become a Terranis.
Terranis will hold. Always.

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I don't get the reference, and Googling "Terranis" doesn't seem to help.

 

[Huginn]

I don't get the reference, and Googling "Terranis" doesn't seem to help.

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it's a reference to Love and Krieg
https://1d4chan.org/wiki/Love_and_Krieg_Spinoffs

 

[Tavarokk]

See, I don't buy that.

The entire Mass Effect series has the galaxy hilariously lightly-armed (I wouldn't call any of the canon fleet sizes enough military assets to adequately cover one star system, never mind thousands) due to operating under pre-WW2 style military treaties, riding high after several millennia on a peacetime footing, and essentially technologically stagnant. It can very readily be read as having been done by design, there's already a vector to do so via - indoctrination - and a vessel through which to indoctrinate everything and the kitchen sink; the Citadel itself.

It can be read - and this fic assumes as I strongly dislike apocalyptic endings and not to put too fine a point on it found the canon ending of Mass Effect eye-rollingly bad - that the Reapers use the Citadel to make the biologicals defeat themselves via stagnation, complacency, disarmament, and the installation of a comically blinkered government prone to 'dismissing these claims'.

The result of an utterly runaway cold-war arms race is a very, very different animal indeed. Quite a lot darker, quite a lot more violent, but VASTLY more heavily armed. By the time of the planned segment about the flashpoint our unnamed Asari Matron fears there are more, and more advanced, dreadnought-class warships in any one of the eight squadrons making up the Sol Home Fleet - effectively the human home defence force - than there were in the entire canon Mass Effect galaxy. The entire combined militaries of every canon Mass Effect race put together would be insufficient to make up one squadron of one fleet of any major player's navy - and the most advanced warship in Mass Effect canon would be considered hopelessly obsolete.

Click to shrink...

Given that the humanity was initially behind in terms of mass effect tech and didn't go for integration into Citadel economic space this time around, are we going to see more divergent technologies like medigel as opposed to "make same things as everyone else, but more and bigger"?

 

[Doghead13]

Given that the humanity was initially behind in terms of mass effect tech and didn't go for integration into Citadel economic space this time around, are we going to see more divergent technologies like medigel as opposed to "make same things as everyone else, but more and bigger"?

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The temptation is to start hurling hard SF at Mass Effect and see what sticks. Bomb-pumped lasers anyone? Casaba Howitzers?

 

[Prince Charon]

The temptation is to start hurling hard SF at Mass Effect and see what sticks. Bomb-pumped lasers anyone? Casaba Howitzers?

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I'm rather fond of both, though I think the latter might be easier.

 

[Tavarokk]

The temptation is to start hurling hard SF at Mass Effect and see what sticks. Bomb-pumped lasers anyone? Casaba Howitzers?

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I'm not sure about the latter, ME armor is pretty advanced still, and kinetic barriers seem to be at least partially effective against particle weapons - Collector particle projectors and Geth plasma weapons pierce barriers much easier than any conventional mass drivers, but there's still some resistance first.

The former on the other hand, now that would be epic. Grazer warheads would be murderously expensive to develop and manufacture, and in peaceful canon times no one would've gone for it even if someone in the command happened to think along the lines of 'countering ME technology' rather than 'making our own more competitive'. But the effect once used, oh we just must see it from the poor victim's perspective >,..,<

Premise for one of the future snips, maybe? We've seen human perspective from the ground zero, now turn for a "preparation for war" human perspective from one of the senior officers that'd let us appreciate the impact on the society, culture and the military (although Shanxi fortress world decription does the latter two partially).

 

[doomlord9]

One very simple but absolutely devastating weapon I haven't seen used is a near FTL sabot missile. It's even perfectly within the capabilities of the ME-verse, no external SF needed.

It's simply a frame with a targeting computer, a power source, an FTL engine, and attachments to hold the projectile(s). All it does is aim at the target from several light seconds/minutes away, getting to that spot via its own FTL drive, then accelerates to 99% light speed, releases the projectile which is just an inert bit of metal, then slows itself down while the projectile continues on it's way at 99% light speed while the missile returns to the launching platform.

This is such a simple way to cause extreme damage, from one-shotting dreadnoughts or space stations with what amounts to a fighter launched missile, all the way up to coring out a planet.

THIS being the classic ME weapon speech, which has a 20 kilo iron slug being accelerated to 1.3% of light speed and impacts with the force of a 38 kiloton bomb. Now, using that math means that a 1000 kilo tungsten rod being accelerated to 99% light speed will hit with the force of-it really doesn't matter because the target is gone.

If they want to get fancy about it, the projectile will have its own power source and mass effect generator inside it. Before being launched it is on super-light mode, but after being launched and before impacting the target it reverses its effect to massively increase the mass of the projectile.

 

[doug89]

It's simply a frame with a targeting computer, a power source, an FTL engine, and attachments to hold the projectile(s). All it does is aim at the target from several light seconds/minutes away, getting to that spot via its own FTL drive, then accelerates to 99% light speed, releases the projectile which is just an inert bit of metal, then slows itself down while the projectile continues on it's way at 99% light speed while the missile returns to the launching platform.

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I like the idea, or even more simply slamming FTL shuttles into them, but I'm not certain they'd work. I think the FTL in Mass Effect works by reducing the mass of the ship. If that's the case then the total kinetic energy shouldn't actually be any higher. Also when the projectile is loosed from the carrier it would leave the mass effect field and immediately slow down to it's 'proper' speed.

I don't know how that is reconciled with mass effect projectile weapons which do maintain their velocity though.

 

[Doghead13]

One very simple but absolutely devastating weapon I haven't seen used is a near FTL sabot missile. It's even perfectly within the capabilities of the ME-verse, no external SF needed.

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Given the tendency of things to slow down on exiting mass effect fields, I'd think a better model would be the so-called kinetic kill vehicle whether relativistic or FTL. This is pretty much the ultimate expression of the missile: it uses being a multi-ton lump of something moving at a high percentage C (or even better FTL) to dump planet-cracking craploads of kinetic energy into the target, which I feel would do exciting things to a Mass Effect kinetic barrier.

In a pinch, one sufficiently motivated person with an FTL-capable starship and little or no interest in continued survival can perform this function, particularly when bearing in mind that the enemy's gate is down. Something like this happened in Mass Effect canon - the Vallum Blast plotline from the Cerberus News Network posts.

 

[Tavarokk]

I like the idea, or even more simply slamming FTL shuttles into them, but I'm not certain they'd work. I think the FTL in Mass Effect works by reducing the mass of the ship. If that's the case then the total kinetic energy shouldn't actually be any higher. Also when the projectile is loosed from the carrier it would leave the mass effect field and immediately slow down to it's 'proper' speed.

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This. ME fields make ships lighter so that they can move faster with less momentum and also fuck with properties of space around the ship so that they don't actually cross or even approach c locally while travelling at FTL speeds from outside perspective. Nothing in that generates real energy that'd be released during impact.

If you want a novel kinetic weapon, you need to come up with a way to generate real momentum more efficient than naval mass drivers.

I don't know how that is reconciled with mass effect projectile weapons which do maintain their velocity though.

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My best guess is that they don't use that principle there, converting electricity into real thrust without involving pseudo-speed at any point.

 

[Doghead13]

This. ME fields make ships lighter so that they can move faster with less momentum and also fuck with properties of space around the ship so that they don't actually cross or even approach c locally while travelling at FTL speeds from outside perspective. Nothing in that generates real energy that'd be released during impact.

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For the second time, your theory does not match Mass Effect canon:

https://masseffect.fandom.com/wiki/..._-_Taetrus.27_Capital_Obliterated_After_Blast

Could potentially be explained as the mass effect field itself impacting.

 

[Tavarokk]

For the second time, your theory does not match Mass Effect canon:

https://masseffect.fandom.com/wiki/..._-_Taetrus.27_Capital_Obliterated_After_Blast

Could potentially be explained as the mass effect field itself impacting.

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In this particular instance, at least, it does.

An interstellar freighter weighting tens, possibly hundreds thousands tons burning full thrust until its out of fuel would produce that kind of impact just fine at a fraction of percent of c of real speed it could reach that way. Using FTL on top of that would not increase that energy any, it'd just make it deliver it to the impact point that much faster, meaning that last second intercept would not be possible unless the space defence forces detect activity at the starting point early on and calculate the course in advance.

Which yeah, still makes it a possible form of attack, but as it does not magic away the need to haul a huge chunk of mass to the middle of nowhere, accelerate it all somehow and accurately hit the mark at the distance of multiple AE with it being pretty much impossible to adjust the aim once the speed is high enough, it's a very situational method. And, indeed, one best suited for destroying concentrations of surface infrastructure.

 

[Doghead13]

In this particular instance, at least, it does.

An interstellar freighter weighting tens, possibly hundreds thousands tons burning full thrust until its out of fuel would produce that kind of impact just fine at a fraction of percent of c of real speed it could reach that way. Using FTL on top of that would not increase that energy any

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On the contrary.

The Cerberus News Network posts directly describe the ship used in the Vallum attack having began a jump to FTL into the planet, arriving at the impact point long before it passed lightspeed. The 'using mass effect equipment' is clearly implied by the bit about beginning the jump to FTL; there is a direct statement that the result would have been far worse if the ship had been able to get closer to (or actually reach) FTL.

For the context of this fic, I'm going to use the explanation that the damage is caused by the ship's mass effect field - specifically, the same thing that creates a kinetic barrier - impacting a solid object with a very high relative velocity. It's most likely going to come up first from a Systems Alliance flag officer, politician, or top-level diplomat as part of a declaration that the Systems Alliance has a no-first-use policy relating to the usage of biological, chemical, or relativistic, weapons, nuclear having been knocked off the list due to nukes being conventional munitions in space.

 

[Tavarokk]

there is a direct statement that the result would have been far worse if the ship had been able to get closer to (or actually reach) FTL.

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Which snip is that?

For the context of this fic, I'm going to use the explanation that the damage is caused by the ship's mass effect field - specifically, the same thing that creates a kinetic barrier - impacting a solid object with a very high relative velocity.

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That works as well, as the source of damage for that would be speed and ME core power rather than speed and ship mass, so how fast or slow its realspace speed was before FTL transit becomes largely irrelevant.

 

[Doghead13]

Which snip is that?

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This one;

https://masseffect.fandom.com/wiki/Cerberus_Daily_News_-_May_2010#05.2F05.2F2010

'The search for survivors in the rubble on Taetrus continues tonight. Only sixteen trapped people have been recovered alive, and experts say the chances of finding more survivors are slim. Bulldozers and heavy cranes are removing debris from the city's four major highways. Only a handful of aerial ambulances have made it to the interior of the rubble. Firefighter Extan Relius says that there is little hope for those in the central crater: "The impact didn't just knock buildings over; it picked them up and dropped them". New calculations indicate that even this massive blow was relatively mild compared to what it could have been -- the ship involved was only starting its acceleration to FTL speeds, and achieved a velocity under that of a mass accelerator bullet before contact.'

 

[SaintMichael95]

Also when the projectile is loosed from the carrier it would leave the mass effect field and immediately slow down to it's 'proper' speed.

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This is just plain incorrect and I have no clue where you got this idea.
Newton's first law of motion:
"In an inertial frame of reference, an object either remains at rest or continues to move at a constant velocity, unless acted upon by a force."

The mass effect field is not a force, it simply lowers or increases the mass of something. A projectile loosed from the carrier is going to maintain its velocity in the vacuum of space when it leaves the ME field, but its mass will return to normal, giving it its actual destructive power. This is backed up by Canon, in fact, with how the ME mass drivers work. If it was as you say, then Canon mass drivers would be impossible, as any projectile fired from a mass driver would immediately slow down the very instant it leaves the barrel. And if we look at FTL drives, then we see that they work by lowering the mass of the ship, which is then accelerated to FTL speeds with conventional thrusters until at the halfway point the thrusters are reversed, slowing the ship back down to sub light velocities.

Direct quote from the wiki:
"When travelling across space, thrusters are applied in one direction for the first half of the trip, then the thrusters are reversed for the second half of the trip in order to reach appropriate speeds for arriving. In 2185, Commander Shepard can have a conversation with Marab on this particular point stating that several people who travel in space forget that the ship must be slowed as much as it was accelerated, hence it will start being slowed halfway to its destination."