The little birds fly in the blue sky. The ocean mirrors the blue of the sky. The deep azure is heaven's ocean. In the blue of the sky, heaven's tears lie. In the tears of heaven, the little bird flies.
— Mato Kuroi's narration from the anime
In 2009, it was announced that an OVA of Black★Rock Shooter would be made based on an original story created by huke.The OVA had a simple plot: Mato Kuroi (voiced by Kana Hanazawa) becomes friends with Yomi Takanashi (voiced by Miyuki Sawashiro) in their first year of junior high school. However, in their second year, they find themselves in different classes and start drifting apart, especially when Mato befriends another girl, Yuu (voiced by Kana Asumi). Meanwhile, in another world, Black★Rock Shooter is seeking out and confronting the mysterious, evil Dead Master. What is B★RS's reason for wanting to fight this Dead Master, and what relation does this have to Mato and her friends?The OVA generated enough interest to make a new anime series, running on noitaminA's timeslot during the Winter 2012 Anime season with a different director. The anime began airing on February 3, 2012, and had a slightly retooled plot: Mato Kuroi enters junior high school and meets a girl, Yomi Takanashi, who seems to be completely distant and aloof. An attempt to become friends with her ends up into a nasty run-in with Creepy Child Kagari Izuriha, who seems to be obsessed with Yomi to Yandere levels. Mato ends up wanting to be friends with Yomi anyway, and meanwhile, Black★Rock Shooter seems to be in another world, still fighting...
All There in the Manual: For all that the OVA diverges from huke's original story in places, you're going to be confused without having looked into it. Black★Rock Shooter is the only character from her world whose name gets revealed!
That said, the OVA's story is written to stand on its own for viewers going in blind.
Alternate Character Reading: Yomi's surname, Takanashi, is written with the kanji "kotori asobi" ("little birds playing") and read "no hawks" as a play on words (see Punny Name below). Discussed by Mato, who thinks it's cool.
Anachronic Order: All of the scenes that happen in the Otherworld, or at least the part with the chain-breaking and the Cool Down Hug, happen after Mato fuses with Black★Rock Shooter at the end.
Mood Whiplash: The various scenes and transition can lead you to that, as well.
Chess with Death: In order to save Yomi without killing her, Mato/BRS had to take a gambit in which she was taken to Dead Master's castle after the latter feels that she has already won.
Chuck Cunningham Syndrome: little Hiro Kuroi. You see him a total of three times: waking up in his bed, telling Mato dinner is ready, and eating dinner with his family. These scenes are very brief and don't effect the plot, so it shouldn't be a surprise if you mention Hiro and no one knows who you are referring to.
Good Scars, Evil Scars: Probably shows the moment B★RS got them, as in the intro scene where she fights Black★Gold Saw she does not have them, and it looks like Black★Gold Saw's final strike hits her in the right hip...
Green Eyes: Yomi has the only green eyes in their school, coupling with Green-Eyed Monster when Yomi grows jealous of Mato and Yuu's friendship strengthening Dead Master's grip on her.
Grey and Grey Morality: People tend to forget that while most would think of Black★Rock Shooter as "good" and Dead Master as "evil", all of the "other selves" are in fact morally ambiguous since we don't know what their motives are.
Shooter is the "hero" by virtue of being attuned to Mato, who just wants to save her friend. But that's about it as far as justifications go.
Here We Go Again: So Yomi is safe and Dead Master is put to rest. Now Yuu is upset about being abandoned...
Huge Schoolgirl: Yomi isn't that tall, but she admits to being self-conscious about her height.
Katanas Are Just Better: Averted, as Black★Rock Shooter's katana doesn't seem to help her much. Its only appearance is during her duel with Black★Gold Saw, and it then fails to reappear for the rest of the OVA. The ★rock Cannon fills the void by pulling double duty as both a ranged and melee weapon by turning into a sword-like object.
Might even be a subversion since she loses with the black blade to a BFS-wielding opponent, and the ★rock Cannon is treated as an upgrade after she merges with Mato.
Late for School: Averted, Mato even gets to enjoy her toast at the table without hurrying and Mato's mother putting a lampshade on it. She does almost miss the train because she's visiting her special place, but the train is on time and it's at school on time she meets Yomi.
No Name Given: Okaasan Kuroi, whom is Mato and Hiro's mother. You only hear Mato refer to her as... well... mother. When she called Mato's cell phone the ID read お母さん.
Even with the release of the artbook B★RS Phenomenon she is given no name, merely the title Mato no Haha (マトの母 Mato's Mother).
Ojou: Yomi, who goes to school on her first day by car (most people walk or take the train) and lived for a while in Germany. Her parents even hire detectives after she vanishes. She has the first kind of Ojou personality, kind and gentle.
Sequel Hook / The Unreveal: For the OVA. Is Yuu Strength? If she is, how did she end up in the Otherworld? If not, who is she? And who was Black★Gold Saw, the girl B★RS was fighting at the very beginning? Black★Matagi and Black★Devil Girl don't show up, nor does Insane Black★Rock Shooter; STR and Black★Gold Saw's appearances are very short. The OVA doesn't really explain who Black★Rock Shooter and Dead Master themselves are, let alone what the Otherworld actually is.
Shout-Out: If you're familiar with both series, you might find a few odd similarities with Ga-Rei Zero- than as can be explained as pure coincidence...
The two schoolgirls Kagura befriends in Ga-Rei Zero- are practically proto- Mato and Yomi. You have the dark-haired, quiet, kindly Oujo and the shorter, more hot-headed one who speaks before they think and has no concept of solving problems subtly.
Thirdly, Yuu. In both series, the character Yuu serves a wedge between the two main characters, be it unintentionally (BR:S Yuu) or unknowingly (GR:Z Yuu). They also have the same name and hair colour, even though one's an old man and the other's a midget Genki Girl.
In the same vein, this could make Yomi, Mato, and Yuu Expies.
Swiss-Army Weapon: We can see the ★rock cannon morphing into a large blade when BRS fought Dead Master the second time.
Technicolor Eyes: Seem to factor very big: Mato has blue eyes, Yomi has green eyes, and Yuu has hazel eyes. These serve as visual cues for their "other selves". Everyone else seems to have brownish/blackish eyes.
Title Drop: B★RS is not even named until the end, when she and Mato merge.
Adults Are Useless: Mrs. Takanashi seems to have an inkling of what's going on between Kagari and Yomi, including the fact that Kagari's paralysis is actually a psychological problem, but lets it continue because she feels sorry for Kagari, apparently more so than she does for her own daughter.
And I Must Scream: By episode 6 Mato is trapped inside Insane Black Rock Shooter, and can barely influence IBRS, who goes on a rampage.
And the Adventure Continues: To an extent. Mato narrates she will grow up with her friends. In The Stinger Black★Rock Shooter says she will continue fighting - though it's implied this will have better results than last time.
Barehanded Blade Block: Strength/Yuu does this to Insane Black Rock Shooter's arm-blade in episode 7. Considering her hands are giant and made of metal/stone, it's not really all that hard for her to do that.
Blue and Orange Morality / Emotionless Girl: Other selves don't have emotions; they almost can't even be said to have Blue And Orange Morality because they act under pure instinct. The exception is Strength, and that's entirely due to the trauma of her real self.
However, it's stated in the last episode that they protect their real selves because they love them.
Body Horror: Black Rock Shooter's transition to Insane Black Rock Shooter is messy.
Book Ends: The first episode starts with a zoom out from B★RS's left eye. The last episode ends with a zoom into her right eye.
Appears mostly in the Otherworld. According to the official website, part of this was intentional to add to its strange, dreamlike quality.
Vehicles and background characters are also CG in the real world.
Darker and Edgier: Than the OVA. Rather than dealing with the subtle hues of The Power of Friendship, characters often and regularly go psycho. In addition, unlike in the OVA, merging with B★RS is an extremely traumatizing experience for Mato.
A Darker Me: A particularly interesting take on this trope. The otherselves are explicitly said to shoulder all the suffering that their human selves are experiencing. They are still the same person, just much darker and violent.
This is interestingly inverted in the case of Strength and Yuu. Once Yuu accidentally teaches Strength to feel emotions, Strength manifests in the real world as friendly, caring, and sociable, completely unlike the rather psycho and unhinged original Yuu.
Determinator: It doesn't matter how much punishment B★RS takes, she keeps pressing on. She might even reach into Implacable Man territory since she doesn't show much of the damage she takes.
More straight to the trope is Mato Kuroi in episode 8. Insane B★RS breaks both of her legs over the course of a savage beating, but once Mato puts her mind to fighting back, she still manages to stand up and wield the Rock Cannon.
Evolving Credits: B★RS is shown in pain, with metal bursting out of the star on her jacket near the end of the opening. After merging with Mato and going crazy in Episode 5, those scenes turn out to be part of the transformation process into Insane B★RS. Her completed form replaces them for episode 6 onward.
First Name Basis: Mato using Yomi's first name with Kagari in earshot causes some problems. Even so, Yomi also uses Mato's first name shortly afterward.
Foreshadowing: Pay very close attention to Yuu for the first four episodes. Notice how she never interacts with anyone besides Mato, Yomi, Saya, or Arata? Or the fact that if you look closely she Casts No Shadow? There's also a moment where she says something to Arata, only to have Arata walk right by without acknowledging her.
It's likely that the following line isn't just filler:
"So for our protagonist to accept death..."
Ultimately this would be fulfilled by Strength.
Strength's color theme is gray yet she has orange eyes. This is a major hint that's something about her is different.
Hope Spot: Episode 5. Mato finally merges with Black★Rock Shooter. All indications are she is about to save Yomi from herself...and after she merges, we find that B★RS has already killed Dead Master. Mato snaps
Improbably Female Cast: Mato lampshades it at one point, noting that her strange dreams of the Otherworld seem to always be about a lot of girls.
It's explicitly stated that the Otherworld is created from the hardships of young girls.
"I Know You're in There Somewhere" Fight: In episode 6, Saya projects herself into Black★Gold Saw in the hopes that Mato will hear her voice from Insane Black★Rock Shooter and stop her deranged rampage. In doing so, she tells her story. Yuu/Strength continues this in Episode 7. She's interrupted, however, when her own identity issue speaks up.
Info Dump: Episode 5 has a massive one from Yuu as she finally breaks out the true nature of the Otherworld.
Leave the Camera Running: After Yomi abuses her cell phone and buries her head in her pillow in episode 4, the shot is held for 30 full seconds with no changes except the cell phone's backlight shutting off.
Meaningful Name: More so than the OVA (see below); the third trailer hints that there will be more wordplay on Yomi's surname of "little birds playing".
Mexican Standoff: Each other-world character does this in a circle during OP credits.
Mind Screwdriver: Yuu —Strength, really— explains what is the otherworld and what are the otherselves. May or may not also apply to the OVA.
Mirror Match: The final battle of the series is Mato as Black★Rock Shooter vs. Insane Black★Rock Shooter.
Mood Whiplash: The second trailer. Watch as they intercut cheerful music with an emotional scene between Mato and Yomi, and Kagari slowly going psycho!
The Spider Tank-type enemy from the PSP game also appears here.
Episode 5: "Do you want to save Yomi?"
Nightmare Fuel: Invoked in the storybook. It ends with the little bird blackens and dies. Who on earth would write a book like that for kids?! Mato's reaction is writing a Fix Fic at the last, blank page of it.
Offscreen Moment of Awesome: Only the start and end of the fight between Black Gold Saw and Insane Black Rock Shooter is actually shown. A great deal of it is implied to be taking place while the audience is watching Saya and Yuu talk.
Shout-Out: The only thing missing from the scene where the original Yuu's house is burning is Sephiroth's theme.
In episode 7 when Hiroyuki Imaishi is in full swing, he also sneaks in Studio Gainax homages. Strength strikes a comically exaggerated Gainaxstance and B★RS sword surfs like it's Daicon VI.
Sigil Spam: The opening gives each of the otherselves, including Insane Black Rock Shooter, their own logos. They never show up in-story, however.
Split Personality: Although the Other Selves seem to be "real", the original Yuu's description of her other self sounds exactly like the common belief about the cause of Dissociative Identity Disorder: creating someone else to take the pain.
Tarot Motifs: "Strength" and "Chariot", so far. (One could stretch and have Dead Master be Death and Black★Rock Shooter the Star. This would possibly make Black★Gold Saw the Devil, based on appearence)
The Stinger: In the last episode after the credits. Strength is revealed to be alive.
Tin-Can Telephone: Kagari speaks to Yomi via one of these, possibly since they seem to live next door to each other.
Trailers Always Lie: The posters and trailers makes it look like Chariot is an important character, and Strength isn't. It's actually just the opposite.
Trailers Always Spoil: Even more obvious than in the OVA, what with Yomi and Dead Master being redesigned to wear glasses. The website makes a token attempt to avert this by not revealing the voice actors for the "other selves".
To be honest, 95% of the people who are watching it have seen the OVA or would have guessed in all of, oh, I don't know, 5 minutes maybe. The series' only worse-kept secret is that Mato is BRS.
On the website, Kagari's pictures on her character page kept switching between her Ill Girl look and Kagari in her schoolgirl uniform - in fact the latter was shown first. The website also showed a figure for Insane Black★Rock Shooter well before she appeared.
Episode 5. Yu might not actually exist. Mato merges with B★RS and finds that she already killed Dead Master. B★RS becomes Insane Black★Rock Shooter.
Episode 7. Yuu and Strength switched places before the story began. Also, Yomi regains her memories of Mato and Dead Master is hinted to be reviving; the same is implied for Kagari/Chariot.
Wham Line: Episode 3: "I don't understand what you're talking about."
Episode 5: "I don't have to kill you yet."
Also in Episode 5: "The manager? I'm the only one for the team"
The cake goes to this line in Episode 7: "Your greeting is rather late, Mato Kuroi. I see my Strength has been relying on you...My name is Yuu Koutari. Strength is down here right now, just as you are."
Black★Gold Saw's is an underground ruined temple littered with chains.
Dead Master's is a misty graveyard. When Yomi's pushed over the edge, the undead overflow in a Zombie Apocalypse.
Strength's battlefield has the most symbolism - it's a constantly shifting puzzle block surrounded by barbed wire, implying Strength/Yuu being trapped and unable to escape. When Yuu goes emotionally insane, it turns into a Lethal Lava Land, going back to Yuu's burning house. Finally, when Strength dies, the puzzle block solves itself and explodes.
There is a white, colorless desert the Otherworld girls spawn from or are discarded into.
One can even find examples of a World of Symbolism outside of the Other World. For example: When Kagari forces Mato to take her to school without Yomi, there's a brief shot of 2 birds flying away from an overhead cable, leaving a single Tiny Bird behind, all alone.