Author's Note: Some people are wondering how the timeline is going to change in this fic, for a few examples: If I put in a Commander Shepard at all, that Shepard is going to be an AI. You already noticed the somewhat different way that 1st contact went. Also, most Alliance-owned locations are artificially constructed habitats. The Alliance also wound up creating handheld energy weapons with about 3 times the damage of canon mass effect guns. To make up for this, the aforementioned energy weapons are power hogs. (The standard assault laser can only shoot 28 times before you need to switch power packs.)
Unknown system
Turian Cruiser Sorry, we ran out of names
Amvus Sylrinus was getting tired of chasing these pirates. This was compounded by the fact that said pirates were opening uncharted relays in a desperate bid to escape. Even worse was that the pirates had somehow acquired a massively up-scaled GARDIAN laser, which they had replaced their cruiser's spinal mount with. They had managed to destroy 2 cruisers and 6 frigates which had been sent to arrest them so far, as that damnable laser bypassed kinetic barriers. He had been expecting it to be a knife-fight weapon, but its increased size had bumped up the range to an unpleasantly long 2,300 km.
That had led to his patrol group being retrofitted with heavy ablative armor to block the laser shots, and then sent to destroy it. Amvus thought 'They must need to discharge their drives by now, right?' as the Batarian-made vessel activated and transited the 4th uncharted relay they had been through so far. As Amvus' 3 cruisers and 4 frigates transited the relay, Amvus realized, to his dismay, that this system was inhabited.
Aurora System
System Defense Command
Alerts rang throughout the SDC as the local relay activated. "Honestly, why did 1st contact have to happen here instead of in some other star system?" thought System Defense Coordinator Cammie Goucher. Well, now she had to deal with it.
Cammie quickly called out "sensors, what can you tell me about that ship?" The received report was "it's roughly 340 meters long, it's got an exhaust trail matching an antimatter-catalyzed-fusion engine, and we're detecting gravitational fluctuations consistent with large-scale eezo usage." Thinking quickly, Cammie asked "what about its destination?" the report from her AI sensor officer Jon was "It isn't clear where they want to go, but they seem to be making a mad dash for the inner system." Cammie, having none of that sent the order to fire Bomb-Pumped X-ray lasers at the contact. She preceded this by loudly exclaiming "They haven't sent a 1st contact message yet, and they're headed straight for the most populated section of the system. Kill them."
An Alliance-produced Bomb-Pumped X-ray laser comes in one of 3 yields, 200 kiloton, 1 megaton, and 15 megaton. Roughly 34% of the energy produced by the bomb winds up in the laser about to cause major damage to whatever the device is pointed at. The weapon fired at the Batarian Cruiser was a 1 megaton version. This means that energy equivalent to roughly 340,000 tons of TNT hit the Batarian Cruiser. It has been proven that energy equivalent to a mere 40,000 tons of TNT is enough to critically damage, and possibly outright destroy, such a vessel. That is when kinetic barriers still do something against the incoming attack, which they could not in this case. The end result being the Batarian ship's complete destruction shouldn't have been surprising at all.
Unknown System
Turian Cruiser sorry, we ran out of names
Amvus chased after the Batarian pirate cruiser 6 light-minutes ahead of him. He was well aware, that meant he was seeing the Batarian vessel as it was 6 minutes ago. He couldn't allow these pirates to attack another group of innocents, even if they were from an unknown race. The illusion of his assistance being necessary vanished when the Batarian vessel was destroyed in a flash of light and his radiation sensors detected a radiation signature consistent with a nuclear weapon going off 30,000 km from the Batarian Vessel.
Suddenly, his cruiser rocked, it had apparently been hit with a smaller version of the weapon that had destroyed the Batarian Cruiser. Thinking quickly, Amvus immediately ordered his communications officer to transmit the 1st contact package. Amvus didn't know it, but his 20 meters of ablative armor (which he had objected to, calling it "unnecessary extra mass") were now a good 19.3 meters thinner in the place where his ship had been hit.
Aurora System
System Defense Command
Cammie's communications team (consisting of 3 AIs and 2 humans) suddenly reported an incoming 1st contact package from the fleet of 7 ships that had recently tanked a hit from a 200 kiloton BPXRL. Seeing as the fleet was now decelerating (they'd turned around to do so when the light from the 1st vessel being destroyed had reached them), and had a significantly different design aesthetic from the recently destroyed vessel, Cammie was content to peg them as 'don't shoot until provoked'.
With that settled, the analysts in Cammie's Intelligence division began working on a translation program, using the data these aliens had oh-so-helpfully provided.
2 Citadel standard hours later
Amvus was asleep when the message was received, and his 2nd in command Heretia was doing her duty. It was in somewhat garbled, but understandable Turian. The message was quite simply "explain your presence here, or leave". Heretia responded with "The ship you annihilated was a pirate vessel we were pursuing." A message returned saying "You obviously aren't a diplomat, could you please run along and get one before one of us does something stupid?"
3 days later, Citadel
Tevos face-palmed, then said "So, you're telling me that a patrol you sent to get rid of a known pirate vessel, wound up chasing them through 4 uncharted relays, and wound up making 1st contact with an unknown species that has practical energy weapons." Sparatus made an affirmative gesture (I haven't got a clue about Turian body language, sue me.) and responded with "after the aliens translated our 1st contact package, their response was to tell our patrol to leave and get a diplomat before either side made a horrible mistake."" And you want me to send someone," said Tevos. Sparatus confirmed this quite rapidly.
Aurora System, 7 days after 1st contact
System Defense Command
System Commander Cammie was quite bluntly, bored. Then a ship came through that relay leading out of Alliance space. After a few seconds it made a transmission saying "we would like to talk in person". Cammie guessed she could allow that, but this ship was designed differently, almost like it was produced by a different species. Still, turning away a diplomat would be a major faux pas.
3 hours later, Aurat
-POV SWITCH: Asari Matriarch Lameka Pesadri-
Truth be told, Lameka had been somewhat surprised to find out that the alien 'city' was in fact a rotating space habitat. Judging from the fact it was 25km long, its use of centrifugal gravity was either to conserve eezo, or because it was a design they created before discovering eezo. Docking with the city went rather smoothly, and she and her entourage had walked down a short corridor before a utility drone had led them to the conference room that had been used for the event.
Now sitting across from the alien diplomats (3 of which were apparently attending via telecommunications), Lameka could understand why they seemed incredulous. Roughly 50% of the alien diplomats could have passed for Asari, were it not for the light brown skin tone and the fact that they had fur in place of head tentacles. The others could possibly slip by, but they had a somewhat stockier build and lacked the mammaries present on the other specimens. Lameka began the discussion with "I am matriarch Lameka of the Asari Republics, the person to my right is my aide Ihossy." One of the aliens attending via telecommunications returned the introduction with "I'm James, an AI citizen of the Earth-Derived Alliance." Lameka's mind came to a screeching halt.
15 minutes later, still in Aurat
Now that Lameka had managed to process the fact that these aliens not only used AIs, but considered them full-fledged citizens, she brought up the next point. Or rather, was jolted out of her daze by James No, the AI, not James, she reminded herself bringing up the next point. The AI who insists on calling itself James said "now that we've managed to snap you out of that, your ships seem rather small, we could easily provide the expertise to upgrade your eezo synthesis processes" Lameka's mind briefly froze up again, but for a shorter period this time. She then decided to bring up a point herself so she could have some time to recover. More specifically, she brought up galactic history.