Fanfic / Fate Genesis

"This is going to be a very different war."

—Saber

Fate Genesis is a Fate/stay night and Sonic the Hedgehog crossover by Cybertoy00.

While on a routine foiling of Dr. Eggman's latest bid for world domination, Eggman's superweapon malfunctions, sending the Sonic crew to the Nasuverse- specifically, Fuyuki, at the beginning of the Fifth Holy Grail War. Sonic and Tails get wrapped up with Shirou's group, Knuckles falls under Caster's influence, and Amy Rose finds Bazett Fraga McRemitz.

But the Chaos Emeralds have also arrived in Fuyuki, setting off a new race for power. And Dr. Eggman is still up to his old tricks. What kind of outcome awaits, now that the Holy War has been set on a new route?

Not to be confused with the Fate/Genesis Roleplay

The cast of Fate/Grand Order reacts to part of this fic in Chapter 8 of Fate Cinema Order.

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This work provides examples of:

• Accidental Truth: When Issei comes across him and Illya, Shirou tells him that she's a relative of Kiritsugu, even mentally applauding himself for coming up with such a clever fib on the spur of the moment. When Issei asks why she doesn't look Japanese, he mentions how Kiritsugu often went abroad as a defense and is startled when Taiga says Kiritsugu was married once.
  • This happens again later when he's watching her use magic to fix the Einzbern estate, noting that it almost looks like she's the elder sibling and he the younger before shaking it off again.
• Actually a Doombot: When Archer faces Eggman on the Death Egg, it turns out to be a robotic body double. Archer is a little ticked that he actually pulled out Unlimited Blade Works over a decoy, even if the robot Eggman was using had items from Gilgamesh's armory.
• Actually Pretty Funny: Kirei has to admit, despite the situation with Sonic causing him stress to try and cover up, watching a deafened Lancer stumble around the church yelling "WHAT" after being hit with a Sonic Boom is kinda funny.
• Adapted Out: True Assassin is the only major character from Fate/stay night to never appear, as Zouken simply forces the still living False Assassin to become his servant rather than using his corpse as a catalyst to summon Hassan of the Cursed Arm.
• Advancing Boss of Doom: Sonic's skirmish with Berserker is mostly a matter of staying out of The Juggernaut's reach.
• Affectionate Gesture to the Head: Cubot and Orbot do this to Shinji when he provides Eggman with critical info. He basks in the praise for a second before shooing them off.
• Alas, Poor Villain: Despite his vile superiority complex and general inappropriateness towards her, Saber can't help but feel pity for Gilgamesh as Eggman drains him dry to power the Genesis Ray.
• All Myths Are True: Eggman realizes this is the case in the Nasuverse when he learns that Berserker is Hercules, who is apparently only a myth in his world.
• All Your Powers Combined: Avenger, due to being created from the Shadow which was in turn made from the sludge of the Fourth War's Grail, hints that he possesses the powers of all the fallen Servants of said War save Saber (since she died after destroying the Grail) and Gilgamesh. He proves this by using Assassin's Presence Concealment, summoning Caster's monsters, and manifesting Diarmuid's two lances with all their effects.
• Amplifier Artifact: The Chaos Emeralds provide so much raw energy that just one is sufficient to provide enough energy to not only anchor a Servant into the world, but give them enough power to fight at near full-strength even without a Master. Caster uses the Chaos Emerald she grabs to boost her magecraft to the point where she can supply energy to herself, Assassin, Saber and Archer at once, while still holding Taiga under a spell that renders her Brainwashed and Crazy, with Illya, who is easily more powerful than most modern mages, being unable to stop it, forcing Shirou to project Rule Breaker to break the spell. Archer, after feeling the energy she's providing him (even more than Rin could), realizes that she'd be unstoppable with the whole set. However, even Caster has to build a grid in order to siphon off the energy without accidentally overloading herself.
  • They have so much energy that they can overwhelm the unprepared mage, Shirou inadvertently tapping into the energy of the yellow Emerald while demonstrating magecraft to Sonic would have killed him without Avalon, and Rin's superior Prana senses nearly cause her to go into cardiac arrest just from briefly touching it, with something similar almost happening to Illya.
  • Earlier, Rin figures out a way to use Power Rings to boost her Magecraft in addition to their usual protective abilities. Servants can also absorb the rings to replenish their energy, which Saber takes full advantage of and Assassin is able to use to leave the Temple for brief periods and even fight Archer.
• Anti-Magic:
  • Rin is able to use Rings to create talismans that disrupt magecraft.
  • Shirou finds Kiritsugu's Thompson Contender and Origin Bullets, which react violently when their target uses magecraft and destroys their ability to use it. When he shoots Caster with one, while it doesn't kill her, the contradiction of a Servant (a being created from magecraft) being struck by a weapon meant to end magecraft's usage all but cripples her and destroys the various strengthening runes she placed on Souichirou.
• Arbitrary Skepticism: Rin and Archer are more skeptical of Sonic and Tails' claims than Shirou and Saber are, despite being a Mage and Servant, at least at first.
• Awesome, but Impractical: Rin mentions a Tohsaka magical device that allows communication between two points, regardless of distance or electricity. Shirou then asks the obvious question, "what if you want to call someone else?".
• Banana Peel: Sonic uses this to trip up Berserker after the giant starts chasing him.
• Batman Gambit:
  • Caster tries to make Saber and Shirou look like the villains to Knuckles by having them attack her when he was nearby. It fails, but she still manages to Rule Breaker Saber.
  • Avenger wants a second Emerald, but Sakura can’t handle the energy of two. So he shows Zouken the one he has to get him actively searching so he can get energy from his Emerald when he finds it.
• Beyond the Impossible: Super Sonic breaks Enkidu, Gilgamesh's indestructible, demigod-proof chains, just by transforming. Even Gilgamesh was briefly stunned.
  • Because the Genesis Ray's cannon is shielded, and the shield won't go down until the very moment it fires, Archer Projects Fragarach to retroactively destroy the cannon. Normally, Projecting a divine weapon would be beyond his abilities, but Archer has Rin grant him his Command Seals' energy to empower him, even if doing so costs him his life.
• Big Bad Ensemble: In addition to villains like Gilgamesh, Kirei Kotohime, and Zouken, Genesis adds Dr. Eggman and Avenger into the mix.
• The Big Bad Shuffle: As a result of the story's Big Bad Ensemble, there's no single central antagonist. Instead, the villain who poses the most immediate threat is generally the one the heroes go after.
• Big Bad Wannabe:
  • Shinji, barely manages to make his debut as a villain before being upstaged by Eggman. Even after Eggman manages to use the Genesis Ray to make him a mage, his lack of practice with his powers and having already tired himself out means that Shirou easily defeats him, and that's after Shirou sees through his claims of being an escaped prisoner because he knows that Shinji just isn't capable of doing something like that.
  • As always, Caster is the first major threat to bite the dust.
  • The apple doesn't fall to far from the tree, seeing as Zouken gets reduces this. As a result of Avenger and the Sonic characters' presence, the old worm gets defeated before he gets the chance to even so much as glance at the Grail.
  • In a shocking twist of events, Gilgamesh. He was most definitely the final enemy in the Fate and UBW routes, but Eggman was one step ahead of him by luring him into a trap that drained him of all his mana, turning him into nothing but mud and dust.
• Big Brother Is Watching You: Lancer notices someone planting a listening device on the church during reconstruction after a robot attacked it, and purposefully leaves Kirei in the dark about it.
• Big Damn Heroes: Illya and Berserker show up just in time to save Shirou from Caster after she steals Saber.
• Bigger on the Inside: Zelretch's Treasure Chest (still in Rin's care) and its occupant are mentioned.
• Big "WHAT?!": Lancer keeps letting these out after being deafened by Sonic hitting him with a supersonic shockwave.
• Blackmail: Sonic manages to take a picture of Kirei and Lancer together, and says that unless they let him go, he'll send it and make sure everyone realizes Kirei is working with a serial killer (getting around The Masquerade on the War since there's no evidence of magic in the pic). Kirei is forced to do so after Lancer doesn't attack Sonic on the rationale that the Hedgehog's speed might allow him to send it before they could stop him.
• Blah, Blah, Blah: When Tails tries to explain how the Power Ring synthesizer works, all Rin hears is "Blah Blah Blah" interspersed with words like "Techno Babble" or "Jargon" (and insults she almost certainly made up in her head).
• "Blind Idiot" Translation: Cubot does one of one of Zouken's grimoires, due to a cheap Internet-downloaded translator.
• Born Lucky: The narration comments that, if Sonic were summoned as a proper Servant, his luck rank would be A+, as him causing Berserker to slip on a Banana Peel and fall a couple of stories onto a car demonstrates.
• Both Sides Have a Point: While arguing with Sonic over his repeated public appearances, Rin is forced to concede that Sonic's isn't wrong for wanting to save lives. However, she knows what steps the Mages Association will take if The Masquerade is weakened enough. (See below)
• Brain Bleach: Shinji has Cubot spy on Sakura's "training session" in order to start understanding magecraft. Cubot and Orbot end up erasing their memories of the experience they're so squicked out, but Shinji (Who in canon took certain liberties with his step-sister) isn't so lucky.
• Brainwashed and Crazy: Caster put a failsafe on Issei in case anyone tried to hypnotize him and check him for Command Seals, causing him to attack Shirou and Illya. She does the same to Taiga, but the Chaos Emerald means Illya can't break her control.
• Brick Joke: Ruby is mentioned as being locked away in a box in the Tohsaka Manor. When looking for a place to store the Emeralds, she's nearly let loose.
• Broad Strokes: The story's plot is a composite of all three of Fate/stay night's routes.
• Broken Masquerade: The government had been looking into things when the events of the Fourth War that made it past The Masquerade started happening again as the Fifth started up, but were getting nowhere, save IDing Saber as the same lady. But then Eggman, Sonic, Tails, Amy and Knuckles showed up, the former two even fighting in the middle of the day on live TV, along with a Saber wearing a Kamen Rider helmet to disguise herself, giving them solid leads and scavenged Egg-tech to track down the magecraft of the city with. As Lancer mentally lampshades when he finds a bug being planted in the church after Eggman attacked it and realizes that some individual figured out that worth keeping under surveillance, it's a kind of Pandora's box situation, with the veil of secrecy that worked before gone now. Before, public officials could just be hypnotized into giving mundane explanations like hallucinations or accidents to events, and while that would still leave at least one person unconvinced, they'd be left with no proof or evidence of any kind. But the blatant nature of Sonic and Eggman means that they're impossible to cover up, even if there was a modern magi strong enough to give Laser-Guided Amnesia to the entire city, which isn't possible, the news feeds are all over the internet and impossible to get rid of (not to mention security feeds that magi forget to erase). Now, people are questioning their entire worldview, and want real answers, not the same old excuses. Kirei is essentially running ragged trying to plug holes in a fracturing dam with his finger, and the Clock Tower is only just being held back from glassing the city in a desperate attempt to bury the evidence by the fact doing so to a large city like Fuyuki could risk a war between Britain and Japan, which would do the magi no favors whatsoever.
• Bruiser with a Soft Center: Berserker is as much as rage and violence incarnate as he was in canon, but when Illya is knocked out by a stray rock, the giant, instead of going even more crazy, just cradles his Master very delicately in his arms and takes her home. Sonic even calls him as such after the fact.
• Bullying a Dragon: Shinji enjoys his The Dog Bites Back moment so much that he even goes as far as to push Zouken out of his way. Keep in mind that Zouken is a powerful mage and Shinji...isn't. Following that, Zouken makes it clear in his thoughts that his first order of business upon attaining immortality is to torture Shinji for the rest of his natural life, and that the only reason he hadn't started the moment Shinji did that was out of shock at the sudden change.
• But for Me, It Was Tuesday: Sonic, Tails, Knuckles and Amy have so many crazy adventures on a regular basis, up to and including being transported to other worlds, that ending up in the middle of the Grail War doesn't faze them that much. Dr. Eggman is a similar case, his reaction when Orbot figures out that they've transported to the Nasuverse is a complaint that other worlds never have anything familiar on TV.
• Butt-Monkey:
  • Lancer gets humiliated by Sonic during their first fight (even having his spear briefly stolen, which is witnessed by the Shirou/Rin alliance), ending up deafened for a while, one of Avenger's monsters latches onto his face during their next, he gets a wasp nest thrown at him, with the wasps going after him when his Protection from Arrows skill causes him to reflexively swing at it, Sonic taking a picture of it…
  • Rin gets the short-end of the stick quite a bit in her interactions with Sonic and the gang, with them ignoring her orders to stay under the radar, getting her Magecraft shown up by Tail's inventions, being kidnapped by Eggman at one point, and going crazy with the realization that all her hard work seems to be going down the drain.
  • Illya gets in on this a bit, particularly with her first run-in with Sonic. She orders Berserker to chase him and then too late realizes she's being left in the dust, runs to the point she exhaustedly lays down on a bunch of lumber at the construction site battle trying to catch her breath and in full view of the people she wants to appear intimidating in front of, and gets bonked on the head by a stray piece of concrete unleashed by Berserker that knocks her out cold when she's in the midst of gloating.
• Call-Back: Mostly done by the Sonic characters, who bring up various adventures they've gone on.
  • Sonic mentions the time Tails fought a witch.
  • Sonic seemingly references either his meeting with Mario for the Olympics or both times ending up in an interdimensional tournament.
  • Sonic thinks that Avenger's monsters (actually Fourth War Caster's octopus monsters) are very similar to other nightmarish creatures that come out at night. Eggman also sees the similarities. Later, he claims that the All The World's Evil has nothing on Dark Gaia when Avenger complains at his lack of corruption from touching it.
  • Sonic prepares to try his hand at sparring with Saber and tells a surprised Shirou and Saber he's not too bad with swords himself, offhandedly mentioning that he was another world's King Arthur. This is before he sees Saber use Excalibur and realizes with surprise she's this world's King Arthur, recognizing her sword despite its different shape even before she calls out its true name.
  • When Rin wonders how could Eggman survive Saber's Excalibur tearing his ship apart with him inside, Sonic remembers that it wouldn't be the first time a giant beam of death tore his ship into two and that he miraculously survived.^{Explanation (Spoilers!)} Perfect Chaos at the end of the game launched the attack towards the Egg Carrier before Super Sonic took the water god down, just in time for Eggman to be seen running away. Not only that, Tails recounts how Eggman survived a black hole after one of his schemes blew up.
  • Amy mentions first meeting Sonic on Little Planet.
  • Eggman Nega is name-dropped.
  • Ruby, or it, as Rin prefers, is mentioned as being sealed away in Rin's chest.
  • Rin compares Eggman's constant attacks to be similar to the Fourth War's Caster team, at least in terms of weakening The Masquerade. It's also suggested that her failure to save some kids from them still haunts her.
  • When Archer tries to mock Sonic's heroism by asking what would he do if the world decided to call him an enemy and tried him for a crime he never committed despite all that he had done as it had for him, Sonic simply replies he'd just launch another jailbreak with the help of his friends.
  • Sonic compares the passageways inside the mountain that Dark Caster made to the Eclipse Cannon.
  • Sonic banishes Avenger from the Holy Grail in a manner similar to how he sealed Erazor Djinn. With Three Wishes to boot!
• Call-Forward: Sorta. Rin has a vision of Illya being adopted by Shirou, which happened in the canon Fate route, from Archer's memories.
• The Cameo:
  • When Sonic gives Lancer an atomic wedgie, he goes so far that he ends up next to the Tohno mansion, where he's witnessed by Hisui. Shiki also pops his head out a window to see what the commotion was.
  • Several characters who were absent during the events of the story show up during the epilogue: Waver Velvet converses with Rin over the aftermath of the Holy Grail War, Yggdmillennia gets name-dropped by Stuart during his conversation Bazett, Amy tells Blaze, Cream and Cheese about her adventures in the Fate universe, Rouge and Chaos are waiting for Knuckles at the Master Emerald's alter with the latter having been serving as substitute Guardian while Knuckles was away, Charmy comes over to Tails' house to return a video game he burrowed, and Big and Froggy are seen fishing with Shinji, who's found himself stuck in Sonic's world.
• Cannibalism Superpower: Avenger implies that he is able to consume the Servants of the Fifth War to gain their powers like he gained the powers of the ones from the previous War, and expresses a desire to do so to Saber and Archer, the only ones he's missing. Rider gets an unfortunate first-hand experience to it, but is killed by Bazett before she's fully assimilated.
• Canon Immigrant: It's stated that the "Mr. Stuart" who appears in this story isn't the same Stuart from Sonic X- rather, it's a Nasuverse version of Stuart.
• Clarke's Third Law:
  • As he explains to Shinji, Eggman doesn't believe in magic, per se, only phenomenon attributed paranormal characteristics due to being poorly understood. Ironically, Nasuverse magecraft does operate under something similar, as magecraft cannot perform feats that would be impossible otherwise through other means (i.e. if technology can't do something yet, like say build a Time Machine, magecraft can't do it yet either).
  • True Magic draws from the Root, and is thus an exception to this, hence why the few remaining Magicians, like Zeltretch, are so powerful. Caster Class Servants are so much more powerful than modern mages despite coming from a time when technology was more limited because back then, True Magic and regular magecraft were less distinct, and there were more paths to the Root.
• Celebrity Paradox: Almost. In an early chapter, Sonic finds a Sega Genesis and plays Altered Beast (1988) on it. He notes that he hasn't seen one of them in years. In either Sonic's world or the fate/stay world, who was Sega using as a mascot in the absence of Sonic? Alex Kidd still?
  • It's noted in a later chapter that at least the original Sonic game was created after Sonic saved the world from Eggman the first time. Apparently "Everybody wanted a piece of Sonic"— Tails notes he has a lunchbox and thermos with Sonic's image in his workshop. Chapter 10 has Amy mention "Fastest Thing Alive" and it being a theme song.
• Chekhov's Gun:
  • In order to fight Caster, who found a Chaos Emerald, Tails, Rin, and Illya make an oppositely-charged fake Emerald of their own to counter its powers. However, it never gets used. Sonic would later use the Anti-Emerald against Zouken, who has bolstered his Magecraft with an Emerald of his own, causing the Mage's destruction.
  • After Shirou uses a Projected Rule Breaker to sever the connection between Ionioi Hetairoi's Heroic Spirits and Dark Rider, Sonic grabs it, unwittingly sustaining its existence using his Chaos Emerald's energy, and uses it to severe the connection between Avenger and his Emerald, preventing Avenger from reclaiming it.
• Cover-Blowing Superpower: When Eggman attacks the school, Saber attempts to lure him away, but he doesn't take the bait, and with so many people watching she is unable to use Excalibur, even without activating the Sword Beam. Luckily Sonic shows up, but that just causes more problems.
• Crazy Jealous Guy: Downplayed, but when Knuckles refers to Gilgamesh as Saber's "boyfriend", Shirou and Archer noticeably tense up and tighten their grips in response while Saber grimaces at those words.
• Crippling Overspecialization: Mages, being Hopeless with Tech and dismissive of it besides, tend to focus on defending against other mages and other supernatural threats, allowing Eggman's robots to just waltz right through Bounded Fields with no apparent issue.
• Culture Clash: Essentially, a common theme of the story is how viewpoints of the characters intersect. More to the point, Sonic's world doesn't have a masquerade; Sonic's crew will respect it on behalf of their hosts (Shirou's group, Bazett), but have no qualms breaking it the minute things get dicey.
• Curb-Stomp Battle:
  • Gilgamesh vs Davy Sprocket; Gil demolishes the robot and a portion of the church, much to Kirei's unhappiness.
  • Berserker vs Dark Zero!Berserker; it goes very badly for Berserker as his remaining lives all get taken out thanks to his predecessor's ability to turn anything he holds into a Noble Phantasm and thus allowing him to just keep switching to new items to fatally injure him, while also retaining all of his combat skills. To add insult to injury, it's Amy's Piko Piko Hammer that finishes him off for good.
  • Sonic vs Dark Zero!Assassin, he uses his Light Speed Attack to thrash them all instantly.
• Damsel in Distress: All three (And a half) of Fate's heroines end up in this role;
  • The battle at the harbor ends with Rin being captured by Dr. Eggman, and ends up needing to be saved from his Flying Torpedo ship by Sonic, Saber, and Tails.
  • Just like in Unlimited Blade Works, Saber ends up under Caster's control for a time, requiring Sonic, Tails, Shirou and Rin to team up with Illya.
  • Dr. Eggman briefly captures Sakura for no reason other than she has a huge pool of energy within her. Sonic and Tails work to help, but she ends up having a Traumatic Superpower Awakening that totals his Egg Mobile de jour. Sakura is later taken to Mt. Ryuudou by Avenger.
  • Illya briefly held captive by Eggman during his raid at her castle before she's quickly freed by Sonic and Berserker. In the final arc, she is kidnapped by Metal Sonic, and is used to power Eggman's machines.
• Decapitation Presentation: Gilgamesh does this with Sella and Leysritt's heads when he shows up to the mountain.
• Didn't See That Coming:
  • Assassin having more than token involvement in the War outside the Temple completely throws Archer for a loop.
  • Gilgamesh making such an early move after Caster's defeat was something Archer wasn't expecting and notes couldn't have come at a worse time.
• Didn't Think This Through: Shinji shortsightedly tells Eggman about the War, which is lampshaded in and out of story as idiotic and a mistake. According to Taiga, he gets his greediness and shortsightedness from Zouken, whom she met at a parent-teacher conference.
• Disappointed by the Motive: Shirou is angered when he learns that Shinji effectively sold out the world to Eggman out over his failings as a Master and desire to be a mage.
• The Dog Bites Back: Lancer, after his humiliating defeats, deliberately doesn't tell his "Master" about a listening device installed in the church by government agents after an Eggman robot demolishes it. After Sonic gets a picture of them together to use as Blackmail to force the priest to let him go, he deliberately ignores Kirei's order to attack, using the excuse that Sonic might be fast enough to send the picture before he could take him out.
  • After teaming up with Eggman, Shinji gleefully turns Zouken's "Reason You Suck" Speech back on him. The only reason Zouken didn't retaliate is because how utterly shocked he was that a piece of garbage like Shinji would get a backbone like that all of a sudden.
• Dragged into Drag: Part of Rin's planned punishment for Archer's betrayal is forcing him into a French Maid outfit.
• Dragon Their Feet: Assassin manages to outlive both of his masters.
• Dying as Yourself: Dark Berserker, Lancelot, regains his sanity as he dies.
• Empowered Badass Normal: Souichirou, thanks to being an assassin further empowered by Caster's strengthening runes. They serve him well fighting Knuckles, but when the runes are forcibly dispelled thanks to Caster being shot by an Origin Bullet, Souichirou ends up injuring himself striking Knuckles and allows the echidna the chance to knock him out.
• Everyone Has Standards:
  • Apparently, any non-Zouken mage would be disturbed by what Kirei did to the fire orphans (at least, in Kirei's own opinion).
  • Shinji may be a Jerkass to the nth degree, but even he is disturbed to the point of throwing up when he sees a recording of what Sakura's "training" under Zouken entails. Orbot and Cubot have a similar reaction, with more pity for Sakura, before erasing their memories of the experience because they're that grossed out.
  • Apparently even Avenger would find the sight of Eggman dancing utterly horrific.
• Explaining Your Powers to the Enemy: Caster does this about Rule Breaker after stealing Saber, as she's completely confident a third-rate magus like Shirou can't do a thing to stop or harm her as she is, allowing Shirou to Project it and free Taiga later, and eventually, it allows him to sever her contract with Saber and take her back.
• Failed a Spot Check: Gilgamesh completely fails to see the signs of Eggman's robots having marched en-masse into the very tunnel he's entering into Caster's territory, mainly due to the fact he deems it both beneath his notice and he's far too occupied with far more "interesting" things such as Saber and the Chaos Emeralds.
• Failsafe Failure: Lancer's Protection From Arrows skill allows him to instinctively dodge or deflect projectiles, but, as it turns out to Lancer's dismay when he learns this, that Protection From Arrows does not take into account whether the incoming projectile is a wasp nest full of wasps or not.
• Fake Defector: When Caster offers Archer a We Can Rule Together speech, he decides to allow her to Rule Breaker him, but doesn't seem to be on her side, as per Unlimited Blade Works.
• False Flag Operation: Stuart's group creates a fake Eggman robot to observe the players of the War.
• Flat-Earth Atheist: As noted in Clarke's Third Law, Eggman takes a very Tony Stark-ish viewpoint to magic, considering it scientifically explainable phenomena that just hasn't been examined to that point yet.
• Fourth-Wall Mail Slot: The Tiger Dojo acts as one, answering questions from reviewers.
• Freudian Excuse Is No Excuse: After his Heel–Face Turn, Lancer explains to Sonic and co. that Kirei only had him kill because he was unable to supply him with mana. Amy quickly mentions the families of his victims, but Lancer can't actually be punished for the murders as he's a Servant. Sonic amends this by giving Lancer an atomic wedgie that stretches so far, it reaches all the way to the Tohno Mansion. He also tricks him into eating a chili dog, causing him to freak out a bit.
• Fridge Logic: In-Universe, Both Sonic and Rin question some of Eggman's design choices in his installations, like installing pitfalls and loop-de-loops. Sonic wonders if him getting overambitious and running out of materials partway through is a component.
• From Bad to Worse:
  • Chapter 11 ends with Caster using Rule Breaker on Saber and grabbing the Chaos Emerald Shirou found.
  • The next chapter has Caster, after fleeing with Saber and Knuckles, then gain Archer's Command Seals, and send a brainwashed Taiga to attack Shirou and Illya.
  • In Chapter 23, while the heroes narrowly escape from the army, Eggman manages to capture what's left of Avenger, and Gilgamesh attacks the heroes again during the fight between them and Kirei.
  • In Chapter 25, Gilgamesh yet again attacks to interrupt the heroes' brief respite at the Einzbern Castle, only for the heroes to realize too late that he was only distracting them when Sakura tells them that Illya was taken by "a robot that looked like Sonic".
• Gilligan Cut: When Tails tells Rin that he's fixed the Tornado, she rejects his invitation to come along on the test flight. The next paragraph has her mentally cursing the Puppy-Dog Eyes of a Furry Fox while seated in the plane's second seat.
• Geometric Magic: Lancer uses his runic magic to trap Sonic in a Bounded Field during the day.
• Goggles Do Something Unusual: Tail's goggles can, among other things, see Assassin when he's under Presence Concealment.
• Go-Karting with Bowser: In an attempt to form an alliance or at least form a ceasefire, Shirou treats Illya to a movie, even though she was still an enemy by that point. This leads to her becoming The Thing That Would Not Leave for the night, and a big surprise when the rest of the heroes discover the little girl who tried to kill them playing Genesis games with Saber.
• Good Thing You Can Heal: Said by Sonic to Shirou after the overload moment in the first chapter. Saber notes that Avalon's power has been doubled somehow.
• Gory Discretion Shot: The narration cuts away when Gilgamesh prepares to kill Sella, Leysritt, Caster and Soichirou in Chapter 17. We only see the aftermath of the former two when he drops their heads before the heroes, and the Tiger Dojo at the end of the chapter shows Medea popping in with Irisviel saying in no uncertain terms Soichirou died with her.
• Grew a Spine / Not Afraid of You Anymore: Teaming up with Eggman gives Shinji the impetus to openly defy and denounce Zouken.
• Had to Be Sharp: Eggman, as Shirou lampshades, had to keep updating his technology to keep up with Sonic and friends.
• Hammerspace: Amy, as usual, startling Bazett.
• Heroic Sacrifice:
  • Lancer puts himself between Gilgamesh and Sonic to buy Sonic time to gather enough Power Rings to go Super Sonic. Needless to say, he does not walk away from the King of Heroes alive.
  • Because the Genesis Ray's cannon is protected by a forcefield that won't go down until it fires, Archer gives up his life to Project Fragarach so Shirou can retroactively destroy it.
• Hero Worship: Shirou, in a subdued way, does this towards Sonic, both for the fact he's legitimately a hero and how Sonic gives him advice and encouragement to pursue his dream of a Hero of Justice instead of berating and looking down on him for it like everyone else he ever met. Archer compares it to a kid realizing Santa Claus is real and notes deep down he's actually a little jealous since he's actually an alternate version of Shirou who only ever got berated and consistently looked down on and never had that kind of encouragement growing up.
• Hijacked by Ganon: Gilgamesh eventually tracks down Eggman and forces his way into his plans. Eggman returns the favor in the final chapter by draining Gilgamesh of all his mana to power the Genesis Ray. However, Avenger ultimately becomes the Final Boss at the last minute when he takes control over the E.G.G. Robo after the damage the heroes inflicted on it caused the Grail Mud that was fueling it to spill out and overtake it.
• Hoist by His Own Petard: Kirei gives Rin a cell phone as Troll gift. Rin gives it to Sonic, who takes a picture of Kirei and Lancer together, and uses it to get Kirei to let him leave. The priest is aware of where the phone came from, and is not happy when he realizes this.
  • In chapter 12, Shirou manages to use Rule Breaker, which he knew enough about to try and copy thanks to Caster, to free Taiga from Caster's Chaos Emerald boosted Brainwashed and Crazy. And in Chapter 17, he uses that very same Noble Phantasm on Caster to take back Saber.
  • In order to control the Shadow, Zouken had Assassin find a Chaos Emerald to bolster his own Magecraft. In chapter 21, Sonic uses the oppositely-charged fake Emerald Tails, Rin, and Illya made on Zouken, and the result caused him and his home to explode.
• Holding Back the Phlebotinum: The narrative states that Saber can't use her Noble Phantasm in Fuyuki because doing so would annihilate the city. Luckily, she can still aim it at targets high in the sky, such as Eggman's airship.
• Hopeless with Tech: Although most magi in the story fit, forgetting about security footage and the like, Rin is the main example. Any time she tries to use tech, she has trouble with it.
• Idiosyncratic Episode Naming: Each chapter is titled after a music track (typically a song, but not always) from either of the franchises involved.
• I Have Your Wife: Zouken tries to take Shirou hostage to force Sakura to control the Shadow, but Sonic intervenes and saves him.
• I Just Want to Be Special: Eggman uses Shinji's desire to be special to manipulate him to his side.
• Immune to Bullets: Servants are immune to conventional weaponry like bullets due to being composed of Prana, and thus they need to specially designed for such combat (Eggman and Tails have built energy weapons that fit the bill due to utilizing Chaos energy, which can interact with Servants). Caster makes the mistake of letting Shirou shoot her with one of Kiritsugu's Origin Bullets while using Magecraft under this logic, which cripples her badly.
• Immune to Mind Control: Sonic and his friends are noted to have a high natural Magic Resistance, to the point Rin completely failed to influence Tails in Chapter 10. Even Caster, a Witch from the Age of Gods, notes that she only succeeded on Knuckles because he was asleep at the time and his own natural gullibleness, and even then she could only influence, not outright control, him.
• In the Blood: Taiga notes in a Taiga Dojo conversation that greed and short-sightedness seem to run in the Matou family, noting that Shinji and Zouken seem alike in that regard after meeting the latter for a conference.
• Inertia Is a Cruel Mistress: Rider attempts to use her Mystic Eyes of Petrification on Sonic when they first fight. The problem is, she takes off her blindfold when Sonic is building up a Spin Dash. Rider is so unprepared for Sonic's momentum that she gets struck dead-on by a spiny ball of stone.
• Internal Reveal: In Chapter 23 Archer shows Rin the exact same pendant she used to revive Shirou, revealing to her that he is Shirou from an alternate future.
• It Can Think: Avenger. In the canon Heaven's Feel route, the Shadow was just a barely-sentient beast that attacked people to feed itself. Here, the Shadow has become as manipulative and calculating as anyone to Zouken's frustration, who notes it wasn't supposed to be able to think for itself, much less talk and plan, and blames it on Sonic and company's arrival (which isn't wrong, because it was caused by Shirou's attempt to Project in front of Sonic that went wrong from a surge of Chaos Emerald energy). Including figuring out that stealing a Chaos Emerald will provide him with more Prana than he could get from Fuyuki's population.
• I Work Alone: Shirou has a habit of doing this, mostly because he feels like he doesn't deserve help after what happened during the Fuyuki Fire. Sonic calls him out on it in Chapter 14, pointing out that even he needs help sometimes, as even he's had, people he couldn't save working alone, and he starts breaking free of it after helping free Sella and Leysritt from being imprisoned upon realizing he can't defeat Eggman's robot Spike by himself and then helping them destroy it.
• Joker Immunity: Sonic and Tails lampshade how Eggman has a knack for surviving situations he logically shouldn't, giving the climax of Sonic Colors as an example.
• Killed Off for Real:
  • Being a Holy Grail War, this is bound to happen eventually, and Rider is the first to bite it in Chapter 15 at the hands of Avenger and Bazett. At least she didn't get eaten by Avenger.
  • Chapter 17 has Sella and Leysritt being killed by Gilgamesh, and though it cuts away he kills Caster and Souichirou, as revealed in the Tiger Dojo omake at the end of the chapter.
  • In Chapter 21, Zouken is blown up by a negatively charged Fake Emerald, with the resulting explosion taking his manor with him. Chapter 22 emphasizes this, as it causes the Crest Worm implanted into Sakura's heart to explode, critically injuring her.
  • In Chapter 22 Berserker is killed by a dark version of Zero!Berserker
  • In Chapter 24 Kirei is killed by Bazett before he can kill Rin.
  • In Chapter 28 Lancer meets his end when charging into an impossible fight against Gilgamesh.
  • In Chapter 29 Archer sacrifces himself to Project Fragarach to give Shirou a shot at destroying the Genesis Ray's cannon.
  • In the same chapter Assassin is the last Servant to go, peacefully watching the Egg Sauser's distruction before his Prana runs out and he fades away.
• Killed to Uphold the Masquerade: The Mage's Association has done this many times, even wiping out entire cities, and Rin is afraid they'll do the same to Fuyuki if the Grail War is at risk of exposure, and is trying to prevent that, including informing the Clock Tower of Eggman's magecraft detecting technology. Bazett is also doing what she can, and notes that the military presence in the city means that the Clock Tower can't just glass it, or risk starting a war between England and Japan.
• Know When to Fold 'Em:
  • After tricking Illya into saying that she doesn't need to steal prana from people to keep her Servant in the war, it was enough for Sonic to decide to bolt since he had no interest in playing tag with Berserker. Illya wasn't so keen in letting him go, though.
  • Caster, even with Saber and a Chaos Emerald, isn't stupid enough to stay in the same place as an angry Berserker.
  • Sonic immediately Chaos Controls everyone on the good guy's team out when confronted by a very angry Gilgamesh.
• Laser-Guided Amnesia: Orbot and Cubot can do this at will, which they do in order to forget about seeing Sakura's "training" which Cubot had previously recorded (and then deleted his own memories after doing so while writing a note and saving a backup). Shinji, who put Cubot up to it, probably wishes he could do the same.
• Leave No Witnesses: Or, as Sonic put it in chapter 10, "Thou Shalt Not Get Caught"
• Let's Get Dangerous!: Lancer eventually gets the go ahead to use his runic magic to catch Sonic in a Bounded Field.
• Let's You and Him Fight: Caster sends information to the Church that allows Lancer to intercept Sonic while the Hedgehog is on his way to Shirou. Lancer suspects that this is a set-up for a grander plan, but still decides to chase after Sonic regardless.
• Let Us Never Speak of This Again: Sonic was supposed to do this for the time Knuckles got his head stuck in a drain-pipe.
• Locked Out of the Loop:
  • Eggman is completely unaware of the details about the Servants or Grail War. At least, he is until Shinji tells him about it at the end of chapter nine...
  • Agent Stuart as well. While Sonic's gang appearing has given his investigation more leads and evidence, allowing him to start getting closer to the truth, he still has no idea what exactly the Fate characters are doing.
• Loophole Abuse:
  • Lancer using his Bounded Field to attack Sonic during the day.
  • Sonic turns it back on them with his Blackmail image of Lancer and his Master together. It's not jeopardizing the War to send a picture of a priest and a serial killer standing together to the media...
  • Shirou and the others cannot directly interfere in Saber's duel with Lancelot, but since Shirou is Saber's mana source, Illya helping give him, and thus her, a mana boost is allowed.
  • Due to his corruption, no matter what wish is made of the Holy Grail, Avenger will twist it into an excuse for mass destruction. But because Avenger is a Servant himself, he can be controlled by Command Seals. Shirou gives Sonic his own Seals so the Hedgehog can force Avenger out of the Grail and seal him into the Throne of Heroes for good.
• Mad Scientist: Eggman of course, but on the Fate side of things, it's noted that a lot of mages tend to fall into this too. One of the major reasons for The Masquerade is to allow mages the freedom to do unethical and immoral experiments without opposition.
• MacGuffin: The Holy Grail and the Chaos Emeralds, of course. Notably, however, several of the villains (notably Zouken and Avenger) have decided to move to grabbing the latter rather than the former thanks to overhearing Knuckles saying all seven can bring forth a miracle.
• Magic from Technology: Part of the reason why Rin has trouble accepting Sonic and Tails' story about being from another world; She equates the warp that brought them to Fuyuki to an act of the Second True Magic, and can't quite accept that a machine can do it. Later on, she concludes that there's a much shorter gap between Magecraft and technology in Sonic's world. When holding her captive, Eggman even manages to siphon off her prana so she can't just bust out.
• Magic Versus Science: Pretty much the Central Theme of the story. Because most mages like Rin tend to ignore technology, Eggman's presence ends up revealing that there are things that technology can do what magecraft and even True Magic cannot, such as getting past Bounded Fields, recording whatever happens, and uploading said recording to the internet for all to see which was what Sonic threatened to do to Kirei and Lancer to get them to back off. This causes most mages to work double time to keep the Grail War a secret from the population. Bazett also finds herself gaining a mild respect (and also fear) for technology. This is also what Rin's rivalry with Eggman is in a nutshell. Like most other mages of the Nasuverse Rin doesn't believe that technology is capable of keeping up with magic. Each time Eggman's creations continue to keep up and show magic up, she grows more and more frustrated.
• Magic Is a Monster Magnet: The devices used to track the energy signature of Chaos Emeralds can't differentiate between them and the energy normal magecraft or Servants, causing Eggman to attack wherever multiple Servants are looking for the Emeralds.
• The Masquerade: Most magi and the pragmatic Dead Apostles in the Nasuverse do their best to maintain their secrecy, often with liberal uses of hypnosis, the former to keep too many people from learning that magic exists, and thus preserve their power by keeping too many people from using their systems of magecraft (as that would split the power to the point of near uselessness) and prevent Clap Your Hands If You Believe from limiting their potential paths for advancement with those systems, as well as make sure they are able to conduct experiments any sane person would consider immoral, and the latter to keep humanity's number advantage from being used against them. The Magic Association doesn't care about atrocities magi commit in the name of research as long as they keep it secret, being perfectly willing to kill off entire towns to preserve that secret if need be, and the mage participants of the Grail War are fully aware that they need to do their best to avoid leaving witnesses or otherwise draw too much attention to themselves to prevent Fuyuki from going that way. The Church also participates in the cover ups, like Kirei in his role administrating for the Grail War, but for more ambiguous reasons.
  • Unfortunately for them, as Lancer notes, Sonic's gang and Eggman appearing means that things have gone to Broken Masquerade already, and almost certainly to The Unmasqued World in the future. It eventually gets to the point where the Association orders Rin and Bazett to capture the Sonic Team.
• The Men in Black: A minor plotline is the investigation of government agents such as Stuart and Twice H. Pieceman trying to figure out what's happening in Fuyuki.
• Minion with an F in Evil: Assassin, as per canon. He's unbelievably personable and happily shoots the breeze with Sonic and Knuckles, as well as mocking Caster behind her back to their faces. As long as they don't make any moves to enter the Temple he never attempts to fight, and even Knuckles is exempt due to his alliance with Caster.
• Mistaken for Romance: Knuckles seems to be under the impression that Shirou and Saber are boyfriend and girlfriend (and while they have gone past the Master-Servant relationship to friendship, it's still not romantic, yet anyways), but Shirou doesn't have time to correct him given Caster's attacking with her Dragon Tooth warriors and already stolen Saber with Rule Breaker.
• Mistaken Identity: Lancelot, with his Mad Enhancement affecting his cognitive abilities, cannot distinguish between Saber and Sonic, due to them both being King Arthur, which Sonic uses to draw his attention.
• Muggles Do It Better:
  • Rin at one point mentally lampshades how technology keeps one-upping magecraft, or at least the close-mindedness of Hopeless with Tech mages. For example, Boundary Fields that fail to detect or even block Eggman's technology because the mages who made them never thought that technology could be a threat to them. Rin also expresses disbelief that Eggman's stronger robots and mechs can fight on a somewhat even ground with Servants rather than being torn apart, but Shirou remembers that Eggman's been fighting Sonic (the guy who's casual running speed breaks the sound barrier) and his other superpowered friends for years and needed to up his game to stay ahead.
  • After Amy narrowly saves her from being hit by a mortar shell, Bazett does an about-face on her opinion of modern weaponry and quickly decides to get a bulletproof vest when she has the chance.
  • Illya lampshades this viewpoint when Eggman briefly has her captive, remembering how her father telling her how the biggest flaw among mages tends to be overconfidence in their own abilities/an assumption that their magecraft made them immune things like rifles and time bombs, which is supported by how he managed to assassinate so many mages while only possessing low-level magecraft himself. Her grandfather, on the other hand, believed that all anyone needed to win was raw Thaumaturgical power, strategy becoming redundant with enough force (hence why they summoned Heracles as Berserker), and spent years trying to instill this viewpoint into her. The situation at the time makes Illya wish that her grandfather hadn't been so quick to throw aside Kiritsugu's views.
  • Rin mentions a magical device her family made that allows communication between two points. Shirou asks “what if you want to call someone else?”, and says that they shouldn’t disregard technology out of hand if they can help even the odds.
  • A much more serious example happens when Rin destroys a military recording device to keep the army from finding out about the Holy Grail War, happily believing that they no longer have any way to record their secrets anymore. Shirou informs her that it was not a recorder, but a transmitter, meaning that whoever set up the device already knows everything even with the device destroyed. Que a battalion of soldiers descending down on them.
• Mythology Gag:
  • Eggman's plot that sends the Sonic characters out of their world is called the Genesis Ray.
  • Sonic ends up in Shirou's yard in a familiar way, and even how they ended up in the Nasuverse is similar.
  • Many of the robots Eggman uses are based on his minions from Dr. Robotnik's Mean Bean Machine and even appear in the same order.
  • Mr. Stuart shows up as a teacher at Shirou's school. After finding the remains of the orphans Kirei used as mana sources for Gilgamesh, he wonders if there's an "E for Everyone" version of him somewhere in the multiverse.
  • Tails uses his Miles Electric to read a document on Ring Synthesis, written by a Sir Charles the Hedgehog.
  • Rin believed that the only way to meet a kitsune is to summon Tamamo No Mae as a Servant.
  • A number of characters mention a cafe staffed by Nekos.
  • On Shirou's decision to go to school without Saber, Rin points out that if they weren't in an alliance, she would have attacked him the minute he stayed behind to clean the Archery Club's room, something she did in the Unlimited Blade Works route and both anime adaptations.
  • Bazett partners up with Amy. Later, Avenger appears and takes on a copy of Shirou's form, and then starts fighting with the powers of the fallen Servants of the Fourth War.
  • Shirou's collection of "certain materials" is hinted at when he's thinking of a place to hide his father's papers.
  • The first casualty in the War is Rider, just like in the Fate and UBW routes of the original visual novel. Bonus points for being killed while using Bellerophon just like in the Fate route.
  • Once again, Sella and Leysritt end up dead at Gilgamesh's hands, just like in the UBW route. Gilgamesh also kills Caster and Souichirou, just like he did in the Fate route (albeit off-screen in the latter's case).
  • (Fake) Assassin ends up getting screwed over by Zouken, just like in Heaven's Feel. This time, however, he's just forcibly taken as a Servant rather than Eaten Alive for the True Assassin's summoning, though not without a lot of grumbling on Zouken's end on how he'd prefer to do it if not for the risks all the Chaos energy being flung around will cause.
  • Eggman mentions that he scrapped Scratch and Grounder when threatening "Proto-Orbot", the gray-casing one that appeared in Sonic Unleashed.
  • Just like in "Sonic X", Eggman uses a giant slot machine to choose what robot he's going to use to attack.
  • Twice is a government scientist.
  • Like in Ataraxia, Lancer is tricked into eating a food item with "dog" in the name, causing him to panic until he gets told that it's not actually made of dogs.
  • Like in Sonic Heroes, Metal Sonic can replicate powers, though Servant abilities are harder to mimic apparently.
  • During epilogue, Stuart recruits Bazett and mentions that they're going to Romania to investigate the Yggdmillennia.
  • Sonic's "house" is identical to the one from Sonic the Hedgehog: The Movie.
• Narrative Profanity Filter: Anyone who's read the original visual novel knows what Sakura's "Training" consists of. But whenever the subject comes up, the story glosses over it and usually only shows the other characters disgusted/horrified reactions.
• Noodle Incident: From the Fate perspective, the constant allusions the Sonic characters make to their past adventures. Also, one time Knuckles apparently got his head stuck in a drain pipe.
  • Whatever happened with one of Avenger's monsters in the Matou library, all we see is Cubot spotting it, then a cut to five minutes later where Shinji is trying to explain things to Zouken, with Eggman somehow capturing the creature.
• No One Could Survive That!: Rin is utterly convinced that Eggman was killed after Saber Excalibur'd his flying airship and reacts with shock and disbelief when Sonic and Tails frankly tell her he's still around. Tails then recounts how Eggman survived falling into a black hole during one of his previous schemes blowing up in his face.
• No OSHA Compliance: Lampshaded with Eggman's design choices for his vehicles and bases, with pitfalls in the middle of pathways, etc., with Sonic wondering if he has to cut back on materials mid-way through to make sure he has enough or something.
• Not a Morning Person: Rin. When Tails sees her, he's kind of shocked to see a veritable zombie instead of her normal self.
• Not Completely Useless: Structural Analysis is often viewed as a rather low-level bit of Magecraft, but Shirou proves it's amazingly useful in figuring out weak points in even the strongest of Eggman's robots, which are capable of taking on even Servants on a somewhat even keel.
• Not Quite Dead: Avenger ends up surviving his battle with Sonic, however he’s on death's door before getting captured by Eggman.
• No-Sell: Sonic's past experience with Dark Gaia's essence means that Avenger's negativity fails to corrupt him.
• Not So Above It All: Saber calls dibs on the Extreme Gear.
• "Not So Different" Remark:
  • When she sees that Shirou came to school without his Servant for protection, Rin becomes irate...even moreso when she realizes that in leaving Archer at her mansion to watch Tails, she did the same thing!
  • Shinji, upon being called a failure by Zouken, points out that even with Magecraft, Zouken failed to win previous Grail Wars, and this time around forced Sakura to take part rather than joining himself, much how Shinji relied on Rider. He takes great joy in claiming Zouken is "Worse than me." According to Taiga, they are also similarly greedy and shortsighted.
  • When fighting Archer, Assassin asks if he is also a fake Servant, feeling something in his strikes.
• Oh, No... Not Again!: This is basically the Sonic characters' reaction to be flung into Another Dimension.
• Only the Chosen May Wield: Since Sonic was once King Arthur, he can use Saber's Noble Phantasms, like Avalon.
• Out-of-Context Eavesdropping:
  • Sakura overhears Rin talking after the latter's realized that the former is connected to whatever's going on with the creatures running around, but unfortunately, since she's communicating with Archer telepathically through their contract, and only saying certain phrases out loud, she gets a very wrong idea of what she's talking about.
  • Shirou realizes that this is also the case for The Men in Black. While they have picked up a lot of information spying on Kirei, without context they have no idea what any of it means. Shirou decides to use this to convince them of the dangers the Mage's Association has towards Fuyuki.
• Outside-Context Problem: Dr. Eggman to the Grail War and Magi society in general. He uses robots and technology far beyond anything else the Nasuverse has, and he's both able and willing to operate in the open and in broad daylight. Sonic and the gang are more heroic and oppose his attempts at world domination, but they're still operating too openly to easily keep under wraps, even appearing on the news and leaving numerous witnesses.
• Paper-Thin Disguise:
  • When forced to confront Eggman in public, Saber takes a Kamen Rider mask from the high school's drama club and wears along with her normal battle dress to protect her identity. Notably, this only fools those who don't already know Saber is a Servant.
  • Similarly, Illya wears a mask of her own when she and Berserker fight against an Eggman Robot.
• Phenotype Stereotype: Sonic lampshades this about Gilgamesh, pointing out that he's pretty blond and pale for a guy from ancient Mesopotamia.
• Phlebotinum Overload: The Chaos Emeralds are so potent that while a magus could tap into their power, doing so recklessly or too much can overwhelm them with their energy.
  • In the first chapter, Shirou is egged on by Sonic to demonstrate his Projection spell. Little do they realize that a Chaos Emerald has ended up underneath Shirou's shed, and Shirou nearly rips his body apart when he unwittingly taps into that power. The narration says the sensation was like his nerves being turned into fire.
  • In Chapter 13, something similar happens to Rin when she tries to tap into the power of the Chaos Emerald intentionally, despite warnings from Shirou not to, in order to show him up. She massively underestimates its power, and the surge of Prana nearly sends her into cardiac arrest due to her finely-honed senses, and if she hadn't dropped the Emerald from the shock it would have done worse. Illya nearly suffers a similar fate when she gets cocky with her own abilities in touching an Emerald.
  • Even Caster isn't immune to this, as her over relying on the Emerald she obtains starts to have a negative backlash on her. She compensates by building a "power grid" to siphon off energy without receiving backlash in her lair.
  • Zouken actually has to restrain himself when Fake Assassin gets him a Chaos Emerald because of the risk of the energy killing all his worms with the backlash.
• Phrase Catcher: The infamous "I hate that hedgehog!" is applied to Sonic by not just Eggman, but also Lancer, Rin and even Gilgamesh. Zouken becomes the latest victim of this before he explodes.
• Porn Stash: Shirou implies that he has one when he's thinking of a place to hide his father's papers, mentioning a hidden compartment in his bedroom.
• Powered by a Forsaken Child: Eggman uses Illya to power his machines in the final arc.
• Power Copying: Metal Sonic is able to analyze Gae Bolg and copy it to a limited extent, though trying so on Avalon fails completely.
• Punched Across the Room: This is how Knuckles pays Caster back for her deception and his imprisonment- by slugging her so hard she goes flying away from her safe spot and into the labyrinth that acts as her lair.
• Pyrrhic Victory: Chapter 17 ends with the gang defeating Caster, saving Saber, and even getting the Chaos Emerald. Too bad Gilgamesh decided to crash the party and killed Sella and Leysritt, Caster and Souichirou are most likely dead at the hands of an angry Gilgamesh after Sonic gets them all out, and (Fake) Assassin is taken by Zouken as a Servant.
• Rage Against the Heavens: Dark Berserker reveals that he is so angry because he realized the gods planned out everything in the legend of King Arthur, so it is all their fault that he, Arturia, and Guinevere suffered so much, all for the gods' entertainment. He declares he will destroy the world for glorifying the legend and to spite the gods.
• The Reveal: Shirou decides to reveal his powers and likely Magecraft in general to the military to get their help in stopping the Grail War.
• Sanity Has Advantages: It is again lampshaded that Hercules would have been absolutely unbeatable in any other class besides Berserker since he would retain his martial skills and sanity. It directly contributes to his death when he goes up against Dark Zero!Berserker, who despite also being insane still has all his combat skills, which when coupled with his ability to turn anything into a Noble Phantasm that can get around Berserker's Nigh-Invulnerability, allows him to thrash Berserker.
• Seen It All: Sonic and the gang have been through so much craziness that they've taken being transported to the Nasuverse with relative ease.
• Scary Stinging Swarm: What Sonic throwing a wasp nest at Lancer plus his instinctive swing at it due to his Protection from Arrows skill equals.
• Science Cannot Comprehend Phlebotinum: The fact that Eggman and Tails' instruments for detecting Emeralds can pick up magecraft, which normal technology cannot, is a major part of the Broken Masquerade.
  • While Metal Sonic can comprehend and even mimic Gae Bolg's time manipulation abilities to an extent, he can't analyze Avalon the same way, since as a creation of the Fairies it's beyond the understanding of mortal science.
• Screw This, I'm Outta Here:
  • Sonic and Tails leave once Illya says she and Berserker don't drain the mana of innocents, though she chases after him.
  • Shinji scrams to a motel when he hears that Eggman can sense magecraft.
  • When Stuart is asking Kazuki about Caster, the former notices the latter, a suspected former assassin and apparently nearly emotion-less man, is blushing, and realizes more about their sex life than he ever wanted to know. Cue quick exit the second he's able to without blowing his cover.
  • As in the Heaven's Feel canon route, when Shinji's Book of False Attendant is destroyed, Rider ditches him.
  • Caster flees with Saber (and an unwilling Knuckles) when Illya and Berserker show up.
  • Sonic uses Chaos Control to allow the group to flee from an enraged Gilgamesh.
• Shout-Out:
  • Cubot believes Berserker is a Stand. He also calls Gilgamesh "the guy from Final Fantasy".
  • When Rin disagrees with Sonic's plan to jump from Eggman's airship while it's in flight, he retorts, "Toolatethiswaysmorefun!"
  • When Eggman locates the energy of the first Emerald, he gloats with an "Excellent!". Cubot then asks if he means "Eggsellent!"
  • After her first encounter with a Badnick, Rin gets a nightmare that reminds her of a certain American movie that has a killer robot from the future.
  • Gilgamesh uses a Mobile Suit Gundam lunchbox.
• Skyward Scream: Shirou does this after Eggman kidnaps Rin while he and Archer are forced to watch Sonic, Tails, and Saber to chase after him to save her, lamenting his uselessness.
• Sliding Scale of Idealism vs. Cynicism: Archer has a bit of a personal beef with Sonic for this reason, namely the fact that Sonic lives in a world where he can achieve the ideal dream of being a "Hero of Justice" that he himself never could. When they fight each other after Archer goes to Caster's side, Archer surprises even himself with how much his usual control becomes compromised as he tries to pick apart Sonic's reasons for fighting only for himself to start doubting.
  Oh, hearing those words ("There's nothing wrong with helping people, am I right?") struck at Archer's core. They struck him more than witnessing his old foolishness in Shirou had. Because from Sonic, those words were more than a coping mechanism. A desperate justification. And it was a reminder of where those ideals had led him.
• Sneeze Cut: When the narration mentions that Eggman's robots aren't known for being deep thinkers, or even shallow ones, Orbot and Cubot suddenly feel depressed.
• Something Only They Would Say: Knuckles does this when Shirou claims to know Sonic. Shirou starts talking about a time when the echidna got his head stuck in a drainpipe.
• Spanner in the Works: As the official summary notes, Sonic is a walking chaos factor, and the presence of him and his friends, as well as Eggman, is throwing the Grail War into turmoil (more so than already at least).
• Spoiler Opening: The author's fanmade opening spoiled Metal Sonic over five years before his first appearance.
• Squick: Shinji after seeing Sakura's "training", vomits. Orbot and Cubot simply erase their memories of the experience.
• Stations of the Canon: Discussed in chapter 10's Tiger Dojo; Because Destiny Says So, Fate characters will subconsciously try to act like they would in their canon routes. However, the appearance of the Sonic characters is throwing everything Off the Rails.
• Strange Minds Think Alike: Multiple characters, from Sonic and Tails to Eggman, refer to Servants as "Magic ghosts".
• Sufficiently Analyzed Magic:
  • This is the distinction point between magecraft and True Magic; magecraft is reproducible by science, while True Magic is beyond that.
  • Eggman likes to analyze the supposedly supernatural, like the Chaos Emeralds, and find means of exploiting it.
• Super-Empowering: Eggman used the Genesis Ray to make Shinji a mage.
• Super Mode: In addition to Super Sonic the final chapter has Saber and Shirou use the Chaos Emeralds as well, becoming Saber Lily and Muramasa Shirou.
• Survivor's Guilt: Shirou's got an intense case of this due to not saving any of the other people who suffered and died around him in the Fuyuki Fire, which fuels both his Chronic Hero Syndrome and his tendency to refuse others' help, since he feels like he doesn't deserve it. Sonic hits this right on the head in Chapter 14, comparing it to Shadow (minus the rage against the world) and telling Shirou in no uncertain terms that while being a hero's noble, he can't save everyone by himself and it's not a weakness to rely on others (after all, he does it).
• Tarot Troubles: Tarot cards are apparently non-magical in the Nasuverse, but Amy's, which led her to Sonic on Little Planet, are, and lampshade the big mistake Shinji made by telling Eggman about the War.
• Technobabble: Rin actually hears the word when Tails tries to explain the Ring Synthesizer.
• There Was a Door: When Knuckles goes to check out the school, Rider is watching, and asks herself why he broke a window when there was a door right next to him.
• The Thing That Would Not Leave: Illya becomes this for the night after Shirou treats her to a Kamen Rider movie.
• Too Much Information: Stuart, when questioning Kazuki about Caster, learns more about their sex life than he ever wanted to know.
• Trapped in Another World:
  • The main premise of the story that Sonic, his friends, and Dr. Eggman's forces have been warped into the Nasuverse, and need the Chaos Emeralds to go home.
  • Shinji's trapped in Sonic's world as his ultimate fate at the story's end. After all the Egg Saucers crashed into the ocean, Shinji survived using an inner tube from an indoor pool's supply closet. Now, he's stuck on Mobius with absolutely nothing; he has no social status or bank accounts, his mage circuits went dormant after Shirou punched him, and his only companions now are Big the Cat and Froggy. Though it's implied that even Big has no sympathy for him after he finished telling him how he got here.
• Undead Tax Exemption: When Stuart tries to do a background check on the Servants who have appeared publicly, such as Saber and Caster, he realizes that he can find no official record of any of them existing. The most he finds is that the credentials Saber used when she entered Japan during Fate/Zero were falsified.
• Underestimating Badassery:
  • The Sonic characters tend to get underestimated, especially the first time around.
  • Magi, in general, are ignorant and/or dismissive of technology, and underestimate how dangerous it can be to them, as Kiritsugu and Eggman have both shown in great detail (the latter especially, since his tech is miles beyond most Nasuverse tech). Bazett makes a full about-face on this stance during a fight with one of Eggman's giant mechs when she nearly gets killed by a stray mortar shell, and the narration notes that one of the things she now wants is a bulletproof vest.
  • Caster underestimates Knuckles' ability to escape from his cocoon of chains, and promptly gets decked on. Though it should be noted that was only possible thanks to Archer Projecting Rule Breaker to break his enchanted slumber in the first place.
  • Dark Rider dismisses Shirou using Rule Breaker as an arrow against him, being initially unaware that it broke the connection between him and his soldiers, dismissing the lesser Heroic Spirits.
• Victory by Endurance: After Dr. Eggman manages to give Shinji the ability to use Magecraft, Shinji revels in his new powers and tries to take Shirou on. But since he has no training and just keeps recklessly throwing out powerful spells, he eventually runs out of energy, allowing Shirou to knock him out.
• Villain: Exit, Stage Left: Eggman is skilled at pulling these off. One actually saves his life against Archer.
• Villain Has a Point: Kirei tells Rin that even if he orders a temporary ceasefire on the war so that the Masters can deal with Dr. Eggman, they would most likely ignore the order and continue fighting each other. He says this happened before when the Caster of the last war threatened to expose magic through his serial killings and was mostly left alone until he became too big of a threat to ignore. Indeed, he's proven right when most of the other Masters and Servants use the chaos Eggman causes for their own personal gain instead.
• Villainous Breakdown: Avenger / Angra Maiyu goes through one of these after Sonic uses Saber's Command Seals to curb his Jackass Genie nature. It's very similar to Robotnik's breakdown from the last episode of his series.
• Villain Team-Up: Shinji and Eggman form an alliance in Chapter 10, Magi. Of course, it's made clear they're both ready to turn on each other when necessary.
  • By Chapter 24, Gilgamesh finally decides to meet Eggman and see if its worth teaming up with him since other options are down for him.
• We Can Rule Together: Caster gives a speech to Archer about this. He then allows her to Rule Breaker him.
• Worf Barrage: As usual, Lancer's Noble Phantasm fails to do anything when he uses it on Sonic, demonstrating the protective powers of the Power Rings. Notably, Sonic still feels the pain of being hit, but the spear doesn't actually damage his body.
• World of Badass: Shirou notes that people with special and powerful abilities, like Sonic's Super-Speed, seem to be common on his world.
• Wrong Genre Savvy:
  • The Grail War operates under extreme secrecy, as The Masquerade details. Rin expected Dr. Eggman to operate under the same rules, but was proven wrong when he attacked the school in broad daylight thinking an Emerald was there. She also underestimates how capable he is at escaping situations where his death should be assured.
  • Eggman himself was unprepared for how pragmatic and ruthless Archer can be, not expecting the Servant to actually try and kill him instead of capturing him. Only the fact he had an escape plan saved him (and taking Rin along for the ride).
• Yank the Dog's Chain: Dark Lancer is Diarmuid Ua Duibhne, who celebrates having a second chance to duel Saber without any interruptions. Eventually, Dark Berserker interferes and impales Dark Lancer, wanting to fight Saber himself. Dark Lancer says, "Why... does someone always... interfere?" before dying.
• You and What Army?: Shirou uses Rule Breaker on Dark Rider to break the connection between him and the soldier Heroic Spirits in his Ionioi Hetairoi Noble Phantasm, Shirou uses this line before Dark Rider notices that they're missing.
• You Shall Not Pass!: When a team consisting of Tails, Knuckles, Amy, Bazett, Illya and Berserker go to Caster's lair to check a spike in Prana, they find themselves in a desert and confronted by three familiar dark warriors who refuse to let them go further.

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