YMMV / Neither a Bird nor a Plane, it's Deku!

• Accidental Innuendo:
  • In "Lounging with Lexi," Alexis tells Midoriya to "eat her weiner" (a hotdog). Midoriya chokes on her phrasing and begs her to reconsider.
  • Pony also has a habit of using "wang" as a slang word.
• Adorkable:
  • Izuku's social interactions are defined by his sheer awkwardness, incredible politeness, and outlandish excitement over all things Hero-related. He has to bow in gratitude while meeting All Might and Firestorm for the first time and is so sweet that it's almost embarrassing.
  • While he initially comes off as stern and professional, Firestorm loves giving corny speeches and is a total fanboy for All Might. He then calls him sickly and old, much to All Might's displeasure, only to immediately backpedal and tell Professor Stein to shut up and let him have his moment.
  • Hisashi can be just as dorky as his son at times, saying that being "super smart" is his job as a scientist. Inko is a worrywart who faints at the thought of her son becoming friends with members of the yakuza by accident.
  • Tokoyami's overly dramatic explanations for mundane things can make him come off as a dork, especially while Dark Shadow is busy making fun of him.
• Alternative Character Interpretation:
  • When Heino Okata/Most Excellent Wonder Bat bought Mount Fuji for Big Science Action, was he just trying to show off how rich he is, or was Tsukauchi right about it being a means of protecting people from the bombs that the Ultra-Humanite left in there?
  • Another in-universe example, was Ashido making fun of Yaoyorozu using a fork and knife to eat a hamburger an attempt at Bathos after All Might's public apology, or was she just making fun of Yaoyorozu.
• Angst? What Angst?: Neither Tsuyu nor Ashido appear to be particularly upset about their bodies transforming into their present states. Tsuyu's case is justified, since it happened when she was a child and was something considered to be normal, but Ashido's transformation happened when she was 12-13 and because she was attacked by a Villain, yet she and the other characters brush it off as not being that big of a deal.
• Arc Fatigue: Thanks to delays in writing and the author devoting time to a few side stories, "Deku's Pal, Katsuki Bakugou" ends up taking about half a year to finish, despite only being one chapter longer than previous arcs. This is actually lampshaded in chapter 13 when Midoriya remarks that the lecture version of Hero Training didn't feel as long as the practical version.
• Ass Pull: Thanks to the nature of the crossover, a lot of changes to the characters and the world come off as completely unexpected and out there. Some of these include Yaoyorozu having two mothers, Uraraka being a Metahuman, Dark Shadow being a Fifth Dimensional being, and Hisashi being Firestorm.
• Awesome Ego:
  • The Ultra-Humanite is incredibly egoistical and petty, threatening to destroy the Tokyo National Museum for daring to house an exhibit of Endeavor. But at the same time, he's a Genius Bruiser powerful and prepared enough to take on Midoriya, All Might, and Firestorm at the same time, only losing due to Midoriya's alien heritage making him immune to the Villain's Quirk.
  • Lexi Luthor is just as self-centered as her grandfather Lex and just as brilliant too. She's constantly looking down on men four times her age because she knows she's five steps ahead of them and generally struts around as if she owns the place (and in many cases she does). She can also terrify Midoriya more than any run-of-the-mill Villain, making him pass out in the snow from sheer fright and unease.
• Base-Breaking Character:
  • Midoriya is this for some people, mostly because of the Angst he feels over being an alien. Some people think it's justified by the way the setting has been setup and distinguishes him from his canon counterpart in an interesting way. Others think he's a baby who has no reason to be as upset as he is. It should also be noted that a lot of it stems from how Bakugou, a highly divisive character in both stories, is the main cause for his troubles.
  • Bakugou is still this. While many people appreciate the Adaptational Heroism he's been subjected to, others hate how he still acts like a jerk despite everything that's happened to him. Even more people simply dislike him for how they feel about him in canon.
  • Ambush Bug is either an entertaining fourth wall breaker or an annoying woman who embodies the worst aspects of Deadpool.
• Bizarro Episode:
  • The first chapter of the sidestory collection to be canon is the Christmas special, and it chronicles Santa Claus visiting various characters around the world before concluding with a fight between Santa and All for One. According to the author, this is an annual affair and Santa is Just Toying with Them.
  • The sidestory "Ring of Earth" abruptly takes things away from the main story to tell a story about Abe no Seimei, of all people.
• Broken Base:
  • Thanks to him being The Scrappy, the author deciding NOT to follow the Fandom-Specific Plot of getting rid of Mineta was met with a bit of arguing on both sides.
  • Midoriya's first costume-as shown on the main page-also caused this. While many people like the design, other people think it looks too cheesy, especially the bunny ear hoodie. This is acknowledged in the story, as his peers tease him for his obvious fanboying for All Might and his costume's cheesy aesthetics.
  • The reveal that Christianity is viewed as a dead religion in present day is either something that makes sense with the information presented about various Gods and deities in the comics or an utterly ridiculous addition to the story.
  • The general Denser and Wackier tone due to including many Silver Age comic book elements is either a draw because of how entertainingly weird it can make the story or a repellent due to how nonsensical some of the interactions end up being.
• Crack Pairing: Going off of the tags used for the story, three of the pairings are Midoriya/Kendou, Uraraka/Nejire, and Jirou/Hagakure.
  • Chapter twenty adds Tokoyami/Ibara and Iida/Kinoko.
• Ensemble Dark Horse:
  • The Eri of the spinoff story Be Humble. The author taking an already popular character and combining her with Shazam! was an instant hit that inspired other writers to start contributing their own stories to the wider multiverse, as seen with The Infamous Man's The Times They Are A-Changin'.
  • Hisashi is also very popular, both for being a loving father, an actual character and for being this story's Firestorm.
  • Of all the members of Midoriya's supporting cast, Alexis Luthor is the most popular thanks to how she alternates between being incredibly goofy and incredibly threatening and how much her dynamic with Midoriya is a changeup from the usual dynamic between a Super and a Luthor.
  • While she has yet to make any physical appearances, Mordred the Shining Knight quickly became popular for being described as an Expy of the Mordred from Fate/Apocrypha.
  • The story's version of Kinoko Komori has been a big hit with fans for making her even goofier than she is in canon.
• Epileptic Trees:
  • In chapter fifteen, the way Jirou talks about the circumstances behind her costume has led to people thinking that she's somehow connected to Mister Stubbs.
  • Ambush Bug thrives off of this. While there was originally a reveal that she was the child Midoriya protected from Bakugou at age four, the next chapter immediately threw a wrench in that by establishing her as an Unreliable Narrator. Not only that, but a lot of her dialogue paints her as someone connected to the Multiverse, maybe even this story's version of the Harbinger.
• Fan Nickname: Readers are already coming up with nicknames for Kryptonian!Izuku, including "Kal-Ku", "Crybaby of Steel" and "Cinnamon Roll of Steel".
• Fanon: Despite author assurances to the contrary, much of the reader-base expects Midoriya to have a The Gloves Come Off moment like his DC Animated Universe counterpart before engaging the Noumu at USJ single-handedly to show just how powerful he really is. This ended up Jossed in the actual story; not only did Midoriya not make a speech of any kind, but he ended up on the receiving end of a Curb-Stomp Battle.
• Fan-Preferred Couple: Bakugou/Alexis is incredibly popular with fans because of the fun dynamic the two have with each other.
• Friendly Fandoms: Many fans of this story are also fans of other popular crossover stories Thieves Can Be Heroes! and Amazing Fantasy. The authors of those stories even gave their approval when the author of this story decided to integrate them into his story's own Multiverse. It's perhaps best exemplified by this fanart of of each story's Midoriya together.
• Genius Bonus: Chapters 5 and 6 are titled "The Übermenschen", literally meaning "The Supermen". This obviously refers to Midoriya himself as his world's version of Superman. But the original use of the term (as explained under the Übermensch page) was to describe someone who is not constrained by human morality and reason in pursuit of their own goals, which perfectly describes the Ultra-Humanite, who feels constrained by human society and believes himself to be a victim of Tall Poppy Syndrome, hence his numerous criminal acts. It could also be translated as Over Man, the name of the Ultra-Humanite's Quirk, which puts him over other human beings by weakening them until they can't put up much of a fight against him physically. Even All Might struggles to fight him while under the effects of this Quirk.
• Growing the Beard: While the story didn't start off poorly, for a lot of people, it really started to come together after the "The Übermenschen" arc when the story started to break away from canon and establish more world building.
• Hilarious in Hindsight: Izuku's passing off his abilities as a Quirk is this when we're introduced to Captain Celebrity in the spin-off Vigilantes, who's Quirk of Flight basically makes him a Flying Brick (though more similar to Superboy's tactile telekinesis).
• Ho Yay: In chapter 18, Mineta gets a full look at Mirio's penis and is actually impressed with what he saw.
• I Knew It!: Although Lex Luthor fit the description of someone who is bald, light-skinned, with a probable supergenius intellect, several readers thought that this individual's plan to break into S.T.A.R. Labs and steal top-secret technology was far too brash and open for Lex's usual plans. Not to mention the fact that with Wayne-Powers around, Lex Luthor would probably be elderly by this point in time. It turns out that the mysterious individual wasn't Luthor, but the Ultra-Humanite, Superman's first supervillain in the comics.
• It's the Same, Now It Sucks!: Some readers are irked by the fact that the early chapters open almost exactly like the beginning of the canon story despite Midoriya's completely different powers, origin, and mindset. This complaint has pretty much died down after the "The Übermenschen" arc.
• Launcher of a Thousand Ships: Just like in canon, Midoriya is this, with fans shipping him with Uraraka, Yaoyorozu, Kendou, Lexi - basically every girl he's come in contact with.
• Les Yay:
  • In Chapter 9, it's briefly mentioned that Uraraka can't stop staring at Katana's midriff.
  • Jirou and Hagakure get a lot of this between them.
    • In Chapter 10, Jirou gets flustered when she thinks Hagakure stripped naked, and Hagakure, herself, doesn't have a problem teasing her about it.
    • She later gets flustered when Hagakure reveals that she voted for her for class president.
    • After it's revealed that Midoriya can see what Hagakure looks like with infrared vision, Mineta asks if she's hot, and Jirou's specifically noted as one of the people looking for an answer.
  • In the Christmas Omake, it's mentioned in the party at Wayne Manor that Stephanie and Cassandra (the two Batgirls before Barbara Gordon took the position back) are making out with each other. Chapter 13 later confirmed that they're dating.
  • The prequel series Zero Year has Uraraka and Saiko Intelli quickly develop a Pseudo-Romantic Friendship with each other.
• My Real Daddy: The Infamous Man's take on this story's version of The Shadow is generally seen as being superior than the one the author wrote to the point that they ended up making it canon to the story.
• Nausea Fuel: The full extent of Bakugou's injuries is revealed in a flashback right before he and Midoriya are set to square off during the Heroes vs. Villains exercise. Bakugou's chest was completely torn open from end to end, his ribs were poking out of his skin and his arm was shattered so thoroughly that they needed screws to hold the pieces together. There was blood dripping everywhere. All of this happened to a four-year-old. It's little wonder that Midoriya is traumatized by what he'd done.
• Paranoia Fuel:
  • Just imagine yourself in Midoriya's shoes. You're an alien on a world that hates aliens. Everyone from small children to fully mature adults would like nothing more than to watch you get beaten into a bloody pulp solely because you're an alien. Your Super-Hearing means that you hear this practically everywhere you go and you're constantly surrounded by merchandise that only encourages violence against aliens. Your only saving grace is that you look human enough to pass for one of them, but that protection only works for as long as you can keep it a secret. So you have to keep this secret every day, minding everything you say or do to prevent others from finding out, lest your adoptive parents (whom you love dearly) get taken away by shady government agents and turned into Unpersons as you'll likely be strapped to a table to be dissected. You have to worry about this possibility every. Single. Day. This is Midoriya's life.
  • Then add in the knowledge there are people who know your identity and are willing to hang this information over your head to taunt you like Lexi Luthor. Even your own teachers meant to guide you towards your dreams may be prejudiced against you for what you are rather than who you are.
  • And then, Himiko Toga turns out to know enough about him to ask "Tell me, did he fly?".
• Rescued from the Scrappy Heap: Many people have commented that this story's version of Mineta is a huge improvement over the original for focusing on his intelligence and self-esteem issues and making his pervertedness less over the top.
• Take That, Scrappy!: For people who don't like Bakugou, him only getting tenth place in the entrance exam was definitely this.
• They Changed It, Now It Sucks!: This story's version of The Shadow is given, to the displeasure of some readers, a Lighter and Softer portrayal compared to the dark Anti-Hero he's usually depicted as. The author said that that part of his character was still intact and that he simply didn't have time to show it, but that wasn't good enough for some people to the point that another person's interpretation of the character was received better.
• Unexpected Character:
  • Chapter 11 unexpectedly has a cameo from Death of the Endless. Not only had the story hardly even alluded to the cosmic and metaphysical aspects of the DC Universe up to that point, but even in the comics, characters from The Sandman (1989) are rarely ever used.
  • Chapter twenty introduces Lori Lemaris, the Love Interest for Superman who hasn't been in the main cast since the 90s.
• Wangst: Midoriya's problems in this story can come across as this, with some people thinking he's too moody to be an interesting character (not to mention how a lot of it stems from Bakugou). He's mostly grown out of this by Chapter 7, but sometimes has brief relapses.