Action Girl: Illya, Miyu and Kuro are young girls who kick the butts of deadly mages and super-powered mythological figures.
A-Cup Angst: The flat chested Sella freaks out in one chapter about her chest being so much smaller than the well-built Leysritt.
Adaptation Expansion: The anime shows the first fight against Bazett in Luvia's mansion. The original manga only shows the aftermath, compressed within a few panels. According to the Word of God, he wanted the animators to extend it.
Illya's father and Shirou's adopted father is Kiritsugu Emiya, a Mage and the protagonist of Fate/Zero.
The Einzburns were an aristocratic Mage family that designed the original Holy Grail War, a battle between 7 masters and 7 servants to get their wish granted. Illya's high mana capacity stems from her rich bloodline and her nature as a Grail Conduit.
The reason why Parallel!Shirou's Magecraft is identical to the Archer Card's is because the Heroic Spirit attached to it is a future version of Shirou himself.
Prisma Illya takes place in an alternate version of the Fate/stay night universe where Fate/Zero never happened. 2wei! implies Kiritsugu and Irisviel murdered the other Einzberns and destroyed the Grail ritual in order to protect this version of Illya instead.
Miyu escaped to the Prisma Illya world from a third universe that borrows from Angel Notes and the Heaven's Feel route of Fate/stay night. Participants of that universe eventually cross over to take their conduit back in hopes of using her to save their dying world.
Arrow Catch: Bazett catches one of the magical arrows fired by Kuro in her bare hands.
Art Evolution: In terms of quality, both of its sequels look much better than the Fate/kaleid. While Zwei streamlined the art style of its characters, particularly the eyes and faces, Drei refined much of it, giving the series a modern look and feel.
Badass: Bazett, who punches out more powerful mages, magical girls, and super powered servants with her bare hands.
Barbie Doll Anatomy: All the girls' nipples and nether regions are entirely non-visible thanks to conveniently steamy baths.
Battle Butler: Luvia's butler, August. In episode 8 of 2wei, he actually manages to hold off Bazett.
Beach Episode: Chapter 18 has all the girls going to the beach for a bit of silly fun.
Beam Spam: A popular strategy for the magical girls is to fire dozens of magical blasts at their enemies. Caster, as in Fate/stay night, takes it to absurd degrees by creating enough magical blasts to fill the entire sky.
The Bechdel Test: Amusingly, inverted in the anime. There are hardly any men in the series (Berserker, some of the Assassins, Shirou and Waver Velvet, Kiritsugu is mentioned but not shown as is the Grand Master of the Mage's association in London) so the odds of two of them meeting and talking about anything other than anything other than the female main characters is astronomical.
Biting the Handkerchief: Luvia bites her handkerchief in disgust while explaining how Sapphire abandoned her for Miyu.
Breaking the Fourth Wall: Inevitable due to the parody nature of the franchise, though this happens less and less as the "seasons" go by. Still, it sometimes results in gems like the following:
Suzuko: "Isn't this main character treatment?"
Nanaki: "This is pretty ballsy coming from a mere supporting player!"
Brick Joke: Luvia, angry about the destruction done by Bazett Fraga McRemitz to her home, states she's going to think up a way to ruin Bazett as revenge. a few chapters later, Bazett's been billed for the damage, had all her credit cards frozen, and been reduced to an ice pop vendor.
Rin and Luvia usually get easily knocked out of fights, despite both being powerful mages. Even their A Day in the Limelight against Saber Alter eventually ends in them getting stuck in a hole underground.
Shirou also ends up getting beaten up in almost every chapter he appears. And in Iri's family hierarchy chart, he's even below the maids.
The Call Knows Where You Live: Illya's parents went out of their way to prevent her from becoming involved in the world of mages. Despite this, Rin and Ruby end up getting Illya involved in collecting the Class Cards from the long abandoned Grail ritual anyway.
Chekhov's Gun: Remember that giant swamp that Rin and Luvia fall into in Zwei? They use it later to catch Kuro.
Clap Your Hands If You Believe: The magical girl powers work entirely on belief. For instance, Illya is able to fly because she thinks she can, and Miyu can't because she keeps getting distracted by the laws of physics.
Invoked Trope in 3rei, Illya realizes the Ainsworth family has taken away the ability for children in their world to believe/dream.
Clingy MacGuffin: A contract with Kaleido Ruby and Kaleido Sapphire cannot be cancelled without their consent. And while they're happy to abandon Rin and Luvia, they absolutely refuse to let Illya and Miyu quit.
Cloning Blues: Kuro is the suppressed memory/destiny of Illya as the Holy Grail conduit given form. She spends a good part of 2wei angry and bitter over not getting to be the "real" one.
Clothing Damage: The heroines' outfits end up getting ripped apart by explosions and debris anytime a fight gets serious.
Illya unlocks a portion of her sealed power during the battle with True Assassin to nuke every enemy in the area in one hit.
Bazett takes on Rin, Luvia, Kuro, Illya and Miyu at once, and the best they can do is fight her to a draw.
Illya with Caster install vs Beatrice Flowerchild and her Berserker install. Illya never stood a chance. Also a bit ironic because normally the The Berserker class is WEAK against the Caster class because of their low magical resistance. Too bad for Illya, Beatrice installed a Berserker that BYPASSESTHIS (THOR).
Dangerous Forbidden Technique: Illya's dual wand wielding at the end of 2wei, which caused internal damage to her that Ruby had difficulties healing. She wanted to use it again in 3rei if she could get her hands on Sapphire, to which Ruby immediately replied that she is forbidden from doing so.
Dark Magical Girl: Kuro, the rival "Dark Illya" who shows up at the beginning of 2wei. She turns out to be Illya's suppressed memories of being a Homunculus built to serve as the Grail conduit, and she'll die if she doesn't have a regular supply of Mana or someone takes the Archer Card that gives her form.
She wasn't the only one either. Miyu is later revealed to be given this role with her backstory, however the main time she was against Illya was at the beginning when she was The Rival.
Demoted to Extra: Central characters in Fate/stay night are demoted to minor roles uninvolved with the main plot. Sakura for instance is just an ordinary student Illya hangs out with, and former Protagonist Shirou is just Illya's clueless big brother.
And then we get to Drei, where Shirou is a legitimate badass.
Dr. Jerk: Caren Ortensia cameos as the school nurse, where she has a tendency to consider patients' injuries 'boring' and ask they get hurt much more badly next time they come to see her.
To add insult to non-injury, she often tells visitors to get lost because "healthy people make her sick."
Illya: "So-so-so-sorry, Miyu! I mistook you for my brothe... I-I mean not that I...! It's nothing like that! It was a dream! Do-ri-mu!"
Everyone Is Related: One page indicates that Miyu, Rin and Luvia know who Shirou is (even though they didn't know Illya.) And he looks like Miyu's brothernote Or rather, he is Miyu's brother in Miyu's home universe, and we never met Shirou's biological family in Illya's universe.
Later we can learn that Kuro is a subversion as she is not evil but merely very dissatisfied with the fact that she took form on Illya's whim, purely because of Illya's paradoxical wish fulfilled by her own magical power, and that she might disappear completely if Illya's wish is ever completely fulfilled. With anger over something this serious, it is of no surprise she tried to harm Illya (to stop her from being able to fulfill the wish completely) and that she is very blunt with her (because she can't harm her now, and is trying to stop her from wanting to be normal again).
Expy: Numerous characters in Prisma Illya are based on people in other Nasuverse works.
Chloe von Einzbern / Dark Illya is heavily based on the original Fate/stay night Illyasviel von Einzbern, as Illya's "original" sealed mage personality in this Alternate Continuity.
Miyu Edelfelt's backstory turns out to be heavily based on Sakura Matou in the Heaven's Feel route of Fate/stay night, as a Holy Grail conduit being abused by her family, and the person alternate Shirou Emiya is willing to abandon being a "Hero of Justice" for.
Fanservice: Some Barbie Doll Anatomy and extremely magical skirts in the first season, and more in the second, of both the girls and Rin and Luviagelita.
Parodied and taken Up to Eleven in the first anime special. Rin and Illya in gym clothes for no reason. Rin and Illya's magical girl forms analyzed in maximum detail. Illya in that cat costume, forced to take sexy poses by Ruby.
Foreshadowing: When Irisviel mentions the Holy Grail War to Kuro and Illya, Miyu gives a surprised reaction. What makes this significant is that no one else makes the same reaction. Kuro's indifference is justified, while Illya gives a proper reaction of confusion. It takes until 3rei for this to get a proper explanation.
The Rider install gives Illya a nifty Eyepatch of Power, whereas the Caster install lacks its trademark hood.
Illya's Lancer install is otherwise identical to the original, however.
I Just Want to Be Normal: Illya has a few moments of this, particularly after the powers sealed inside her start acting up.
This infuriates Kuro, and Illya realizes this isn't just a slap in the face to her existence, but to Miyu as well.
Miyu herself is someone for whom her brother wished this, since at that point she was too broken to wish for it.
If It's You, It's Okay: Kuro needs to be regularly supplied with mana in order to keep from disappearing, and this is essentially her attitude when she explains to Illya that the two of them are the most compatible for the process. Also see Intimate Healing below.
Imagine Spot: Luvia has one of those when Irisviel invites she, Rin and Miyu to spend some days at the Emiya household since the Edelfelt mansion was destroyed by Bazzet. Her line of thought involves sleeping together with Shirou, having a baby and marrying him.
Invisible to Normals: Averted. When some of the girls from school first see Illya transformed, they recognize her instantly and assume she's doing some bizarre cosplay. Of course, they might have been somewhat distracted by the fact there were two of her...
In 3rei, the castle of Ainsworth is invisible to anyone not in its close vicinity.
Ironically, Illya's own leitmotif, Die Lorelei is absent from the anime. But then again, she does get her own Emiya theme, so...
Let's Get Dangerous: When Ruby and Sapphire grant "guest" access to Rin and Luvia when they're up against Saber Alter. One would never believe that Magical Girls could be so Badass.
Lighter and Softer: Fate/stay night is a visual novel where the main characters are constantly hunted in a dramatic Mêlée à Trois, putting their lives at stake. This manga, however, is light-hearted and focusing on magical girl antics. Illya is a healthy young girl with a normal lifespan, is enjoying herself immensely when she's not running for her life, and her and Shirou's parents are alive.
The second "season" called 2wei is mostly the same, being full of light-hearted moments, even though there are some more serious elements like Kuro's existence, Bazett's appearance, and the fight against the 8th card.
The third "season" called 3rei is much more serious. There are still a few comedic elements, especially in the Omake, but between Miyu being held captive by The Magocracy, Miyu's universe's Shirou being held captive and tortured by the ones who captured Miyu, and Illya's party being trapped in a Crapsack World, it is debatable whether this trope still applies.
Limited Wardrobe: Averted, although Rin and Luviagelita tend to wear outfits of the same style as their standard outfits in the visual novels (Luviagelita wears frilly things, Rin tends to show off the Zettai Ryouiki in most of her outfits).
Literal Split Personality: Kuro was born from Illya's memories up until she was 8 months old, having already gained the ability to understand communication and knowledge. The memories were sealed so that Illya could have a normal life.
Mundane Utility: As the blu-ray exclusive OVA shows, magical girl transformations can be used for other things — like dancing. Specifically Miyu uses Sapphire to dance more naturally during her class' turn in the Sports Festival. Oh, and it adds sparkles to her routine too.
Mutually Exclusive Magic: Mages have the same limitations that they do in the rest of the Nasu Verse. Magical Girls aren't as restricted; they're not quite Sorcerers, but they can easily perform feats that would cripple or kill an ordinary magus, with the catch being they require the approval of their Empathic Weapon. And then there's whatever is sealed inside Illya; the limits aren't yet apparent, but it's shown the ability to crush Epic Spirits with relative ease, her Magical Girl status seems to be waking it up, and she's not happy.
Mysterious Past: There is... something sealed inside Illya, that her maids know about. A vast power that goes way beyond "Magical Girl" and that the recent nonsense seems to be waking up. When she remembers pieces about it, she tries to go back to forgetting.
Miyu also is a "something." It's mentioned that she required an Undead Tax Exemption; and like Illya; she can manifest cards within herself. Kaleido Ruby comments that if Miyu had used her true power in their initial sparring, Illya would have been creamed. It then asks if Illya knows just what Miyu is. In 3rei it is revealed that she is Shirou's "original" sister, and the Holy Grail of her world.
Rin starts out with the class card for Archer, her Servant from the game. Her rival, Luvia, starts out with Lancer's, Archer's most common rival.
Rin and Illya inverting the famous 'Are you my master?' scene, with the standing figure ordering the sitting one to be her slave.
Rider is the first Servant to be defeated on-screen. As usual.
The "I will 'go home'" from Rin's letter.
The "Liner" in Kaleid Liner Prisma is a reference to a race of evolved human beings in TYPE-MOON's Angel Notes. The entire premise of the alternate universe in 3rei is based on Angel Notes' setting.
Stella puts on her Fate/stay night outfit after being jealous of Miyu's own maid uniform.
Caren Ortensia from Fate/hollow ataraxia is the nurse at Illya's school, and even uses her "Cloth of Magdala" on occasion.
Zelretch is serving as the master of Rin and Luvia, while Waver Velvet is acting as his assistant.
The song "Emiya" plays when Illya installs the Archer Card.
The relationship between Kuro and Illya mirrors that of Shirou and Archer in the "Unlimited Blade Works" route of Fate/stay night.
The Saber Install chant is the same one that is used for the Servant Summoning Ritual of the Holy Grail War.
Illya's Zwei form increases her power by using her nerves, along with other organs just as Shirou originally used his organs / nerves to power his Reinforcement ability in Fate/stay night.
In 3rei, Illya with the Lancer and Kuro with her archer abilities recreate the Lancer vs Archer fight Shirou witnesses early in Fate/stay night.
The Mapo Tofu ramen shop owner in 3rei is Kotomine Kirei from Fate/stay night.
Darius repeats some Melty Blood rants about stage plays.
The entire premise of the alternate universe in 3rei is based on Angel Notes' setting.
Ruby and Sapphire have the same mannerisms and voice actresses as Kohaku and Hisui from the Tsukihime series.
In 3rei, Shirou combats Angelica, the wielder of the Gilgamesh Install by countering her sword bullets with Projected copies. In an effort to end the battle quickly, he even attempts to invoke Unlimited Blade Works.
Oh, Crap: In 2wei, the magical girls give a collective one when Gilgamesh brings out Ea. In fact, this is pretty much the default reaction to Gilgamesh doing anything.
Offscreen Moment of Awesome: During the epilogue of the first season, Luvia makes off with Rin's cards. The epilogue chapter ends with a Sequel Hook— Rin caught up to Luvia and beat the crap out of her, reclaiming all of the cards, but is forced to remain in Japan for fighting.
Painting the Medium: The second season begins with the girls wondering why their outfits have changed, and the only explanation given is something along the lines of 'because a new storyline started'.
Panty Shot: Loads in the second season, although it's not the focus of the manga.
Parody Sue: Miyu Edelfelt is one of these at first appearance. She is hilariously good at everything in school; confusing the teachers with her advanced mathematics, creating breathtaking masterpieces in art class, and cooking elaborate feasts in Home Ec using only a single frying pan. Getting a time of 6.9 seconds in 50 meter dash is also impressive for someone her age.
In 3rei, it is revealed that she isn't as perfect as she appeared to be, courtesy of psychological issues—whatever was done to her before her brother managed to send her to Illya's world made her into an ace, but left her really broken and unable to dream. Still doesn't explain her inhuman cooking skills, but that one might be running in the family.
Power Copying: The cards provide the user with a specific Noble Phantasm when included in the Kaleidosticks. Installing them into oneself allows the user to gain a fraction of the Heroic Spirit's power and abilities by overwriting one's own existence at the cost of being unable to use the Kaleidostick's powers.
Powers in the First Episode: Wether the first chapter or first episode, Illya gains Magical Girl powers by forming a contract with Kaleido Ruby. This also tells the readers/viewers that this story is a lot different than the original VN.
Power-Up Letdown: The Assassin Install is actually weaker than Illya's standard Prism form. This gets lampshaded by Kuro, and acknowledged by Illya, before switching back.
Pragmatic Adaptation: The anime adaptation avoids or outright cuts out any reference to Illya a Grail conduit from the supporting characters like Sella, Liz, or even her mother Irisviel. In the latter's case, the conversation the two had in the anime was completely given a different context — instead of Iri obliquely telling Illya not to be afraid of her powers, she gives her advice on trying to understand why Miyu acted the way that she did.
The 2nd season is an aversion. Mysteries brought up by the first season and left a mystery are explained in episode 6. What was the golden-eyed personality that engaged the Assassin and Saber cards? That was Kuro, Illya's original personality who was sealed by Irisviel and released through the Archer card. How did Illya perform feats like overpowering the Saber Card's Excalibur and detonating a massive amount of mana? It's because Illya/Kuro is a conduit to the cancelled Grail and her bloodline carries a magical background from her mother's side, granting her the mana capacity to perform said-feats.
The most obvious pairing are Illya and Miyu, who are Fireforged Friends and share quite an amount of intimate moments.
A more down-toned, sort-of Belligerent Sexual Tension relationship is fairly obvious between Luvia and Rin; the two can't stand each other very much but in truth they rely on each other much more than they'd like to admit. Though they obviously don't kiss.
Season 2 adds Kuro, who is a lot more open about everything, making the relationship between Illya and Miyu a lot more complicated. The fact she randomly walks around kissing everyone she meets (which somehow are only girls) pretty much confirms this trope. After all, Girl On Girl is Cute.
Rummage Fail: In 3rei, Gilgamesh attempts to withdraw Vimana from the Gate of Babylon, but is unable to find it (his treasury having been split in two and divided between himself and Angelica). He casually tosses out a number of legendary treasures while rummaging around for something that might be useful in the situation.
Schmuck Bait: While looking at job ads, Rin gets a little too blinded by one position's absurd pay rate to notice that the job requirements are so specific that really only she could possibly fill them. Congratulations, Rin-san... you are now Luvia's personal maid.
Schrödinger's Cat: Illya's parents Kiritsugu Emiya and Irisviel von Einzbern are both alive in this continuity, while both have been long dead in the original Fate/stay night and only appeared in person in the prequel.
Miyu's very existence is this, as everything points to her being Shirou's actual biological sister. This means that in every other continuity it's likely that she died during the same fire that engulfed the city at the end of Fate/Zero.
Screw Yourself: Being partially Archer, Kuro's feelings toward Shirou are technically this, while also being a case of Brother-Sister Incest. And then in Drei, Kuro and Illya are getting too chummy...
Serious Business: Illya vs. Kuro in an epic, life-or-death, magically powered... game of dodgeball.
Sella gets really intense about weight loss.
And now 2wei Chapter 12 brings us Epic Cake-baking.
Epic food judging too.
Shirou:(with an ultra serious look on his face) "I can't tell a lie about cooking!"
Sequel Hook: The anime has one. In Episode 10, Bazett walks through an airport after the credits end.
At one point, Kaleido Ruby suggests they 'explore' an alternate dimension by 'reducing it to nothing with a 'Lyrical Grade' magical blast'.
The way that Illya solves the issue that same chapter is probably a Nanoha reference as well: As she proceeds to kill all of True Assassin's incarnations at once, as mentioned above, with a Nanoha-style 'level everything at once' blast. Starlight Breaker on steroids.
In Episode 10 of anime, Illya uses Nanoha's "Zenryoku Zenkai!"note Maximum Power!/Full Power! Catch Phrase when firing a point-blank mana blast at the Berserker Class Card.
In Chapter 9.5, Karen-sensei is showing putting sugar into green tea. Six of them. At least unlike Lindy, she didn't put milk in it...
Sink or Swim Mentor: So Miyu has a mental block against flight that she really needs to get over. What's the most sensible way to go about it? Well, if you're Luvia, the obvious answer is 'throw her out of a moving helicopter'!
What makes it worse is that it fails.
Skinship Grope: Pops up a few times, including one awkward example wherein Illya gets felt up in the bath by her mother.
Sorting Algorithm of Evil: Averted. The major enemies of each arc vary widely in their power scale and morality. The 7 Cards are feral and vary wildly in strength, Bazett is neutral and about on-par with the Cards, Card!Gilgamesh is insanely powerful, but lacks higher judgement beyond his instincts to pursue the grail. The Ainsworths are the closest that an antagonist in the series gets to evil, but they're below Card!Gilgamesh on the power scale and their actions are to save humanity.
The Spock: Miyu's weakness, a lack of imagination in a world where this powers up your magic.
Stay in the Kitchen: Inverted with Sella in the first episode. She actually wants Shirou to leave the housework to her so that he can be a better big-brother example to Illya. You could say that she wants him out of the kitchen.
Teeth-Clenched Teamwork: Rin and Luvia despise each other, but they are thoroughly competent when they actually manage to put aside their differences and work together. Granted, it takes a threat of the highest caliber to actually make them do so, and they go right back to shouting matches and brawling the second it's dealt with...
Tsundere: Alternate universe or not, Rin is still Rin. And to make things worse, Illya is almost completely incapable of bringing out her deredere side.
And Sella, although she seems to reserve her 'dere' for Illya exclusively. Poor Shirou in particular gets an almost unending stream of hostility.
Transformation Is a Free Action: Averted by Illya in the second episode. Her transformation seems to work in real-time as seen from Rin's perspective, including the music and light show.
Illya: "I'm back." Rin: "Why did you bother hiding yourself?" Illya: "Because it's embarrassing."
Also averted when Illya installs the Archer Card. The only reason Illya completes the transformation is because Saber is interested in what Illya was doing.
Averted again in Episode 9. Berserker tries to attack Miyu while she's priming her Saber install.
Averted in Episode 1 of the second season. Rin and Luvia can be heard struggling while Illya and Miyu complete their transformations, and Rin also lampshades how they should skip the Transformation Sequence entirely.
Truce Zone: The gang encounters Bazett during the Beach Episode, who is working off the damage she did during their fight as an iced treat vendor.
Undead Tax Exemption: Luvia cooks one of these up for Kuro when her presence is revealed to the rest of Illya's school. Interestingly enough, Luvia comments that they had done the same thing for Miyu...
Unwanted Harem: It's looking like Shirou's putting one together, and he isn't even the main character. Illya, Kuro, Rin, Luvia, and maybe Miyu... that's five, four of them added in the space of one chapter. Dude doesn't even have to try anymore, does he?
And then the very next chapter is a flashback explaining how Rin and Luvia fell for him... while also adding Sakura to the harem! He really doesn't have to try anymore!
It's Nasuverse, a male lead will always have a harem.
The beach episode ends with this: First, Nanami calls out Rin and Luvia for getting between her sister and Shirou (Noodle Incident, bag of frogs); then, in order, Luvia, Rin, and Issei lay claim to Shirou. The four of them corner Illya to make her decide which one gets Shirou. She then runs away, thinking about how SHE wants Shirou. Finally, Ruby comes by with a "Love Potion", gives it to Shirou, and it turns out to be a Truth Serum. Cue Shirou passing out and, in his sleep, clearly defining the Unwanted part, stating what he dislikes about each of the first four suitors. Let's go over this: Illya, Kuro, Nanami's elder sister, Rin, Luvia, and Issei. As well as possibly Sakura and Miyu. Poor guy really can't catch a break.
Visual Pun: When Mimi watches Illya kiss Kuro in Chapter 17 of 2wei, the scene switches to a bouquet of lilies (i.e. yuri) that their other classmates were discussing.