The way I avoided that with Nobody Dies is that I kept it in a close, but alternate version of the canon timeline. But that was the kind of story that I wanted to tell. You don't want to do that with the setting- this is closer to Aeon Natum Engel than Nobody Dies. You're taking the ideas of Eva and putting them in a more hard scifi/Half Life verse. I say go for it.
—Gregg Landsman about this fic
Ascension is an Alternate Universe Fic crossover between Neon Genesis Evangelion and Half-Life, written by rookie writer amitakartok. It's basic premise is simple: what if the Black Mesa Incident was Second Impact which happened in the US instead of Antarctica? And what if it happened two years ahead of SEELE's schedule, completely messing up their plans? Well, if Shinji and Warhammer 40K is the love child of Eva and Warhammer 40,000, Ascension is the love child of Half-Life, Tengen Toppa Gurren Lagann and Nobody Dies, attempting to fuse the Real Robot and Super Robot genres into a coherent whole.The fic itself picks up in 2041, 23 years after the Combine has been ousted from the planet. While humanity still haven't recovered completely, they harvested and reverse-engineered most of the leftover Combine technology for themselves. In these times, a certain Kaworu Nagisa transfers to Tokyo-2 after his old school takes issue of him having taken lessons from Kamina. Shortly after his arrival, he gets into the middle of several incidents which seem to be connected to a mysterious classmate of his, Rei Ikari. And what's the deal with those Humongous Mechas built illegally by the Artificial Evolution Laboratory?
All Planets Are Earth-Like: heavily averted. It's specifically mentioned that Earth is the only planet where humans can survive without EVA equipment.
Case in point is Proteus: while being a Goldilocks planet, it has an unbreathable nitrogen-helium-CO2 atmosphere, no surface water and slightly higher surface gravity. The former two however is being corrected via terraforming.
Heavy Worlder is also averted. Children born on Proteus are mentioned to have a noticeably higher risk of developing skeletal deformities as simply being born on a planet with 1.1g does not make a human adapted to it.
Ancestral Weapon: the Beretta Shephard gives to Asuka as birthday present is implied to be the very same gun he carried back in Opposing Force.
Apocalypse How: Class 1 as per the Half-Life verse. Had the Combine occupation lasted another decade, it would've devolved to a Class 2.
America is implied to have gotten away with a Class 0, what with being sealed inside a time-dilation field preventing the Combine from invading.
Axes At School: Rei routinely brings her armory to school. Hikari is understandably freaked out.
Bang Bang BANG: averted. Unit-01 firing it's gatling cannon shatters every window nearby.
Beige Prose: English isn't the author's first language, plaguing the early chapters with this. It got progressively better as the story progressed, though.
Big Damn Heroes: Asuka intervenes in the Shamshel battle to give Kaworu time to undig himself. Neither knows who the other is.
The first half of the Iruel battle ended up with Asuka and Kaworu getting bailed out by a Mysterious Protector.
Bilingual Bonus - Kaworu is trilingual (English the official language of the Confederacy, GermanKaworu lived in what was originally Austria before he moved to Japan and Hungarian one of Kaworu's friends in Austria taught him it) and he specifically messes with people by making remarks in something other than English until Lilith calls him out on it
And then he gets to be on the receiving end of it when Rei and Tabris converse in Japanese specifically because they know Kaworu can't understand a word of it.
Binary Suns: it is mentioned in the first season that one of the human-inhabited systems is a binary system with all the planets orbiting one of the stars. Also a case of Alien Sky as every planet's night side experiences a midnight red glow from the smaller star for a full half year.
Bi the Way: Asuka and Mari are both bisexuals but are hiding it from their parents. Cue Hikari freaking out.
Boom Stick: Kaworu accidentally blows up a chunk of the city when he stabs the Lance of Longinus into Shamshel. The Angel is completely vaporized by whatever the Lance did to it.
Bungled Suicide: Rei tries to kill herself when she realizes Kaworu is a better pilot than her, only to be foiled by him. She does jump off the building they're on but he falls after her, grabs her and teleports the two of them across the street into a thrashcan to cushion their landing.
Christianity is Catholic: pointedly averted. Early on, Yui mentions Rei being a Christian but when Asuka asks her which denomination, Rei gives an unexpected answer: she's not part of any denomination because she wasn't baptized, therefore none would accept her.
Word Of God states the author himself is Lutheran but didn't want to take sides or write about things he has no clue of.
Sahaquiel: when Kaworu blinded her, she started wildly flailing around with her plasmawhips to keep him out of knife range until she thinks up something better.
Ramiel: since it couldn't shoot and use an AT-field at the same time, it launched several attack drones to do offense while he shifted to defense. Justified in that it was being remote-controlled by Bardiel.
Gaghiel: you're an aquatic creature and is fighting against a flying opponent who can simply go higher if you try to catch her? No problem, you've got a Breath Weapon for that.
Deus ex Machina: sort of. Kaworu has no weapons to attack Shamshel with and the Angel's whips are preventing him from getting close enough for an unarmed attack. His Eva is damaged and about to run out of power. And then the Lance of Longinus erupts from the ground right next to him... Subverted for reasons revealed much later.
Dirty Communists: the Confederacy. Kaworu's not exactly fond of them.
Disaster Democracy: how the Confederacy of Man started off before being covertly overtaken by SEELE
Door Stopper: on the way to becoming one. The fic is already over 150,000 words and according to Word Of God, we're only about one-third into the story.
Explosive Overclocking: the F-type equipment's railguns have an adjustable power level. Repeatedly firing it on maximum output is... not really healthy for the machine's superstructure.
Flawed Prototype: Unit-00 still has this distinction. The only reason it can keep up with the newer models is because the pilot is just that good.
Four Philosophy Ensemble: Kaworu is the Optimist, Shephard is the Realist, Yui is the Cynic. Rei is somewhere between the Cynic and the Apathetic.
Frickin' Particle Beams: upon realizing conventional bullets don't have enough kinetic force to penetrate AT-fields, the AEL quickly equips their Evangelions with handheld Tau cannons. These ones do work... but not much better.
Full Frontal Assault: the famous Rei-exiting-shower-to-find-someone scene is repeated with a twist: Kaworu is on the receiving end and Rei attacks him with a sword
Gatling Good: the Rheinmetall MK225 triple-barreled rotary autocannon, carried by Durandals; has a 20mm caliber and is designed to pierce synth armor. Kaworu pulls out an Eva-sized version against Shamshel but as expected, it doesn't do squat.
Gratuitous Japanese: prior to the rewrite, the first season had plenty of this.
Meta Mecha: F-type equipment, a powered armor for Evangelions
Mini Mecha: the Mk-III/B Durandal, designed for urban combat. A Fragile Speedster in that it can shrug off small arms fire... but not much else, preferring to avoid being hit in the first place instead.
Imported Alien Phlebotinum: lots of Combine technology was abandoned when Overwatch fled the planet. Humanity put all that to good use...
Insistent Terminology: whenever someone speaks Japanese, the author uses tenshi instead of the canon shito to refer to the Angels on purpose.
Kung-Fu Sonic Boom: the result of two AT-fields colliding, powerful enough to knock down a Humongous Mecha weighing several thousand tons from kilometers away:
Lighter and Softer: while the Half-Life universe is even more of a Crapsack World than the Evaverse, Kaworu doesn't have the same emotional baggage canon!Shinji does
Magnetic Hero: Kaworu uses almost the entire arsenal of said trope.
Type 2: Asuka doesn't really like him but fights alongside him anyway because she doesn't have a choice in the matter.
Type 4: Rei becomes interested in him after he foils her suicide attempt.
Type 5: most of his vigilant group follow him because they sympathise with his ideals.
Magnetic Weapons: several. Basically, if there's a large single-shot cannon that's not mounted into a multi-barreled configuration, chances are it's a railgun. Ships have spinal-mounted versions while in Chapter 26, Rei uses an oversized Rheinmetall 250mm SrK L/75 Donnerlanzebolt-action sniper railgun (with some Gun Porn).
It is a Period 8 transuranic element that cannot fit onto the periodic table of elements due to being exotic matter.
There are four known isotopes, all of them solid at room temperature. The base isotope is a yellow crystalline material used in various utilities. The second isotope and the only other one occurring naturally is a light blue fluorescent crystal. The third is a chemically inert violet crystal. The fourth is the only one to have received its own name (xenite) and is being researched as a possible power source.
It reacts violently to being bombarded with high-energy particles by releasing gravitational waves. Only a few kilograms of the material can generate waves powerful enough to damage steel and concrete structures and open microfractures in the fabric of space-time.
It has an atomic mass of over 300 but due to the adverse reaction to mass spectrometers, its exact mass and atomic number cannot be determined.
Waygates generate wormholes by using specially prepared crystals of the first isotope that contain artificial impurities of certain superconductors. These are capable of near-instantaneous wormhole generation across interstellar distances when electrically charged.
The second isotope can destabilize interdimensional portals to the point of implosion.
There are however a few that stretch belief. Especially gravimetric sensors, Waygates and of course the Evangelions themselves.
Mook Horror Show: Rei exterminates the entire crew of a truck convoy to get their cargo, taking advantage of the night and the thick fog to play Deadly Guest with them.
More Dakka: F-type equipment is focused on heavy fire support with no less than 48 barrels of autocannon, missile and railgun pointed at the target.
Obligatory Swearing: averted in an attempt to stay realistic. Touji is the only person who swears a lot (much to Hikari's annoyance) with Kaworu adding a Precision F-Strike here and there but other than these, no one says so much as a "shit". Well, Shephard does but Yui is always quick to reprimand him for it.
Organization With Unlimited Funding: averted. The AEL had to become a PMC to avoid getting bankrupt after Kaworu racked up such an impressive collateral damage against Shamshel.
Portal Network: there's one that links an unspecified number of systems together. It's pretty slow (less than a parsec per day) and can't operate in gravity wells (the Earth gate dodges that issue by being anchored inside the Earth-Moon L1 Lagrangian point).
Secret Identity: Kaworu made sure no one outside the AEL except four people knows what he's doing for a living. Especially not Asuka.
Shown Their Work: the author apparently likes to flaunt the effort laid into worldbuilding.
Sibling Team: Kaworu and Rei in the second season.
Space Fighter: the SF-144 Nova sixth-generation space superiority fighter. Can't leave the atmosphere on its own but is confirmed to be carrier-based and capable of surviving atmospheric reentry. Kensuke gleefully lists off its capabilities when he sees one in the second season, including the lack of stealth capabilities.
The Little Detecto: gravimetric sensors. They detect the minuscule spacetime distortions caused by the presence of mass and therefore cannot be confused by stealth. Lots of tightly-packed objects however WILL make them ineffective, hence the need for radars. AT-fields and dark energy are instantly spotted from a VERY long distance due to their spacetime warping properties.
The Metric System Is Here To Stay: The Confederacy uses the metric system. Shephard once uses US pints out of habit but an author's note includes the equivalent in litres.
Chapter 8: Breen was a member of SEELE and was using the Combine to expedite Instrumentality. Obviously, it didn't work out.
Same: the AEL already had Kaworu's genetic records and Yui knows who he is.
Chapter 18: the Lance of Longinus was the Borealis' cargo.
Chapter 20: Kaworu and Rei has a mutual past but neither remembers the other.
Chapter 26: Kaworu and Rei are genetic siblings.
Season 2 chapter 11: the Source the Evangelions are based on is the Nihilanth.
Vigilante Man - Kaworu was expelled from his previous school because he helped a younger boy being bullied by the principal's son. Helped as in, put the bully in hospital. And he's about to continue right where he left off by rallying a group of schoolmates behind him to enforce their own sense of justice.
Virtual Soundtrack: mainly for the fight sequences. The author also compiled a list of opening/ending themes, one pair for each season and an additional ending for each Season Finale.
Wagon Train to the Stars: Project Exodus. Millions of humans were relocated to self-sustaining colonies in other star systems to prevent extinction.
Waif-Fu: The Present has Rei taking out two armed thugs without breaking a sweat.
Wave Motion Gun: the Tau cannon they borrow for taking down Ramiel blasts through the Angel and two hills before flying off into space and hitting a satellite on the horizon. Furthermore, the F-type equipment's railguns are confirmed to be capable of hitting stratospheric targets when turned to sufficiently high power (see Explosive Overclocking above).
Averted in chapter 14: Shamshel is dispatched to find out where the hell did Sachiel go. Then played straight when the Angels probe the Evangelions' capabilities from different directions instead of charging in.
World Half Full: although humanity still hasn't recovered from the massive asskicking suffered at the hands of the Combine, they got good things out of it too - the technological level has never been so high and the establishment of the Confederacy brought world peace (albeit an uneasy one)
World of Badass - Kaworu's principle in life is striving to create this
Year Inside, Hour Outside - the Barrier created by Second Impact is a giant dimensional anomaly that envelops most of North America, making time go at a factor of six, i.e. there's 2005 inside but 2041 outside.
Zerg Rush: the military tries this against Sachiel, doesn't really work
In the second season, Kaworu challenges Israfel to single combat. The Angel recognizes that it's outnumbered and responds by summoning a whole army of insectoid Starfish Aliens.