In 2157 a Citadel Council exploratory vessel is tasked with opening a dormant Relay into unknown regions of the galaxy. What they find is something they never expected. What happens when two civilizations centered around different technologies clash?
The most followed Halo/Mass Effect crossover on fanfiction.net, Mass Effect: Clash of Civilizations by Eterna1Soldier describes the buildup and ongoing first contact between the humans and alien races of Halo and the alien races of Mass Effect.
Notable for its relatively slow pace, approaching the twentieth chapter before diplomats from either side even meet each other, it is nonetheless an extremely popular fanfic.
Mass Effect: Clash of Civilizations provides examples of:
- Adaptational Heroism: Saren. His Jerkass personality and bigotry against alien species is still present, but without Sovereign's influence he has not turned against the Citadel Council.
- Adventure Archaeologist:
- Liara, who begins the story working on an actual archaeological dig before being recruited to study the new alien species and its artifacts.
- Technically, as someone who is helping with the expedition and analyzing the technology, Tali counts as well.
- A.I. Is a Crapshoot:
- Downplayed. The geth remain a dangerous threat from the Mass Effect series, but UNSC AIs are more stable and functional members of their society. They run the risk of going "rampant", but are not inherently unstable.
- Averted with the Huragok, as they are technically AI's, but the worst they do is be totally uninterested in non-technology matters.
- Alternate Universe: Apart from the crossover nature of the fic, which removes the human Systems Alliance from the Mass Effect history completely, there are other divergences from the primary Mass Effect canon. The batarians became a rogue state 200 years before the start of the series after conflict with the asari, instead of only recently abandoning the Citadel conventions after conflict with humanity, and the Citadel Council has modified their laws regarding the activation of dormant Mass Relays. On the Halo side, the orbital installations on Harvest weren't destroyed as thoroughly — the lift still works (though there are implications that this is just a replica of the original station, such as a recording announcing that this place is a memorial, the lights and air still working, the very clean state of the station, and the station noting that the last people to come there only came about two months previously).
- The Battlestar: UNSC cruisers and Carriers. The Eternal Light of Sol, a Forerunner Fortress-class warship, takes it beyond Eleven.
- Boldly Coming: Discussed by various members of the UNSC and the URS as they talk about various inter-species relationships. Also leads to some initial confusion when Captain Alenna initiates a meld with Ensign Duran to learn his language. His confused attempts to explain what happened to other UNSC personnel sound like him saying they had just mated... and to be fair, Melding is a way that Asari mate. It's just that it can be used for other things.
- Call a Rabbit a "Smeerp": A creature almost indistinguishable from a dog is native to Thessia, known as a "shia", which the Asari likewise keep as pets. They are not just similar to dogs, they are dogs (Or at least a close species relative).
- Canon Welding:
- Forerunner Metals are revealed to be the same as the those that make up the Relays and the Citadel.
- The Reapers were created by the Precursors, and were ordered to leave the Orion Arm of the galaxy alone for two hundred thousand years, which is why the Forerunners and the ancient human empire were allowed to develop to the point that they did.
- The Dreaded: ONI soldiers are seen this way by the rest of the UNSC, since they work for an organization known for skirting the line of ethics at best and they don't answer to UNSC chains of command. Captain Miles notes when they appear that everyone else seems to try and hide behind him.
- Dyson Sphere: As in canon, the world of Trevelyn is a Forerunner-constructed example, currently under the jurisdiction of the UNSC.
- Energy Weapons: Played straight for the UNSC and Former Covenant. For species that use the Mass Effect though, Kinetic Weapons Are Just Better. Both sides do have points, and the weapons tech on each side is very effective in its own ways.
- Fantastic Racism: Saren is condescending and rude to Tali because of her quarian heritage and dismisses the humans as a brutish and irredeemably violent species before they had even made first contact. Both examples of racism are however at bare minimum understandable. The quarians unleashing the geth on the galaxy is a point of racial tension that even Garrus brought up in canon, and the Migrant Fleet does have legitimate problems that cause trouble for the rest of the galaxy (strip-mining planets for needed resources, dropping criminals off on inhabited worlds without the permission of their governments, etc). Humans are somewhat less reasonable, but given that the only evidence of humanity that Saren knew about was a massive battlefield and a burned, scorched garden world (something anathema to the Council races), it was an understandable first impression.
- Earth-Shattering Kaboom:
- When the Sol's primary weapon was tested on a Brute base, it atomized the planet and many of the enemy ships in orbit, which was not what anyone was expecting.
- The crew of the Hades Gate think that the unknown (Citadel) races did this to one of the moons and put a space station in its place. Turns out that it wasn't a moon, it was just ice and rock that collected around the dormant relay, and activating it caused the coating to shatter (as was the case with Pluto's moon of Charon in canon).
- First Contact: The premise of the first arc of the story. Ironically, the contact occurs over Harvest, the same planet where the Human-Covenant war began, as the Council forces study the technology and remains of the battles for control of the system.
- First Contact Math: Notably averted. Each side has their own method of deciphering language, neither of which involve mathematics.
- First Contact Team: The crew of the Hades Gate as well as Liara, Alenna, Saren, Mordin and Felix.
- For Want of a Nail:
- Though Tali and Liara become friends, without the authority figure of Commander Shepard to smooth over bigotry problems, Tali feels resentment, bordering on outright hatred, towards the Citadel Council. She circumvents Council law to surreptitiously send data to the Migrant Fleet, whereas in the main timeline she had enough faith in her superiors to ask for permission to do so, and would even abide by their refusal if they said "no".
- Saren is a jerk, but ultimately reasonable person who hasn't betrayed the Council due to the First Contact War never happening, so his Freudian Excuse and contact with Reapers likewise never occurred.
- Green-Skinned Space Babe: The asari, as pointed out by Ensign Duran.
- Humans Through Alien Eyes: The story is often told from the perspective of the Mass Effect races, although not exclusively.
- Human Subspecies: It turns out that the asari do not just look like humans, but are in fact a species relative. They, and a species native to Thessia known as a "shia", are genetic cousins of humanity and dogs, respectively. It's later revealed that they were created by ancient human civilization shortly before its destruction by the Forerunners and seeded on a world far beyond known space, in the hope that humanity would endure in some form far from the sight of its destroyers.
- Jerkass Has a Point: Saren is an arrogant, racist bastard, but he takes his assignment as head of security seriously and makes valid points of observation. He's correct in assuming that Tali is up to something suspicious when he catches her in the communication station, as she's illegally transmitting data to the Migrant Fleet, and his armed standoff with ODST troops prevents a bloodbath after Captain Alenna makes a meld at the worst possible time.
- He also points out a rather significant point — the first contact message that they received only had one species in it (humans, specifically), despite the war zone they are studying having the wreckage of two species' ships. From a security standpoint, this is worrying.
- He points out to Tali that most likely, the unknown race with such amazing tech (humans) wouldn't necessarily share it with a race of homeless beggars who couldn't do anything for them in return and whom they barely know.
- Saren also correctly states, after Liara and Tali go on and on about how wonderfully advanced this race of beings is who built all of this, that the only evidence they have of the various species' cultures is a humongous graveyard of warships, as well as a planet that shows evidence of orbital bombardment-a huge no-no to the Council. While the scientist and engineers are acting like starfleet officers, gushing about the wonders of the universe, he's making the case of: "Hey, we know nothing about these guys, and what little evidence there is makes them look very dangerous.
- Liara chides Saren for assuming the worst, and assuming that these "humans" will be dangerous. It's worth pointing out that that is his job.
- Mental Fusion: The asari use their melding talents to quickly learn languages, and to help those they meld with learn their language. One of the UNSC's Huragok is able to tap into one of the meld-ee's neural jack, copy the Citadel languages, and provide everyone present with a translator.
- Mile-Long Ship: Every UNSC ship above the weight of a light cruiser and every Covenant capital ship. Averted mostly with Mass Effect ships, as per canon. And like in canon, this is justified- Mass Effect fields on objects need increasingly huge power supplies the larger the object you're trying to have an effect on is. Ships larger than a kilometer (as in dreadnought-class) would require so much eezo that it would be impractical. UNSC and Covenant (and Forerunner) ships, which do not operate under eezo-based tech limits, circumvent this.
- Mistaken for Profound:(...)Liara (...) was utterly intrigued with the architecture. (...)Every now and then she would see words written on hanging signs, above doorways, and on walls in some strange alien language. Perhaps they were words of great wisdom or knowledge.
'Dining to the Left (Kids eat free!)'
'Do not spit over docking ledge. Thank you'
- Averted when they find the statue of Sif. That actually is profound.
- The Mole: Tali, sort of; she doesn't have any loyalty to the crew or the Council, only to the Migrant Fleet, so she feeds them intel on humanity and the other discoveries the crew makes.
- Normal Fish in a Tiny Pond: Many of the technologies that the UNSC take for granted, such as artificial gravity, faster than light tech, and crystal computational devices, are utterly amazing to the Citadel Races, largely because they did this without any Element Zero, which was thought to be essential for the first two technologies, at least.
- OOC Is Serious Business: Hev, who is conservative even among its own oblivious-and-not-excitable kind, after discovering the kinship between asari and humans.
- Poor Communication Kills: Barely averted because cooler heads prevailed in time. When Alenna tries melding with one of the humans, they try to separate their colleague from the strange alien who appears to be covering him in weird blue energy. Then Liara uses her biotics to stop them, as interrupting a Meld can have fatal consequences. Upon seeing an alien using psychic powers on their captain, people start reaching for guns, Saren holds the human captain hostage... but fortunately the Meld ends swiftly enough for Kyle and Alenna to explain to both sides what is happening.
- Powered Armor: The MJOLNIR Mark VIII, made from Forerunner metals that are lighter and stronger and it can be used by non-SPARTANs.
- Proud Warrior Race Guy: The Sangheli ambassador, whose purpose seems to be "Let's try to make diplomacy as difficult as possible by being innocently insensitive."
- Reasonable Authority Figure: Councilor Tevos has a far more realistic expectation of what possible contact will bring than her two colleagues.
- Rubber-Forehead Aliens: Asari and humans are almost visually identical, with only a differing skin color and the presence or absence of hair. This is a huge surprise and shock to both species, as though they are each familiar with aliens of the same general bipedal shape, they have never encountered such an exact parallel before. It turns out the asari are a Human Subspecies.
- Schizo Tech: The UNSC from the Council's perspective. They have space elevators, massive ships and incredibly advanced computing technology but still use slugthrower weapons with comparatively limited ammunition (Council weapons are also projectile-based, but they are more akin to railguns and have effectively unlimited ammunition).
- Shown Their Work: Ship sizes, technology and weapon effects are taken from Mass Effect and Halo wikis and official sources. Eterna1Soldier has pointed out specific sources when some fans have criticized the sometimes staggering size imbalance between the different universes.
- Space Elves: The Asari, but this isn't much changed from canon.
- Starfish Alien: The Engineers.
- To a smaller degree, the Hanar, which are noted as looking somewhat similar to the Huragok.
- Stealth in Space: UNSC Hades Gate can cloak itself, becoming both invisible to light and to other forms of detection. This was an established technology in-universe, as Halo: Reach and Halo: Legends proved.
- There Is No Kill Like Overkill: The UNSC not only sends in entire fleets into the neighboring systems of Harvest, but also contacts the Sangheili, who in turn send in a Supercarrier, which by itself is powerful enough to conquer a planet on its own. To cap it off, the UNSC also sends in the Light of Sol, a Forerunner Fortress-Class Ship powerful enough to obliterate planets. All of this was a reaction to a small Turian patrol entering Harvest's orbit. Justified in-text, as the last time that humanity met a conglomeration of alien races banded together for mutual cooperation and defense it triggered a three decade-long war of annihilation that reduced mankind to a mere fraction of what it once was. Them showing off the massive resources at their disposal and their military capabilities is their way of saying "We don't want war, but if war comes, we are ready for it, and we can make you sorry you ever so much as looked funny at us."
- That Didn't Happen: Miles, after discovered that Duran probably slept with a female Sangheli.
- What Could Possibly Go Wrong?:"And besides" Valern said, "even if they prove to be hostile to us, they don't even use element zero. How advanced can they be?"
- What Did I Do Last Night?: Ensign Duran is very adamant that he did not sleep with a Sangheli that one night....probably.....he thinks. Maybe.
- What the Hell, Hero?: Saren gives Tali a vicious, yet accurate, calling out when he catches her sneaking info to the Migrant Fleet, pointing out to her how incredibly stupid of an idea this is.