The Loch Ness Monster is really just a Kelpie that shapeshifts into a sea serpent when it wants to. Before the legend of Nessie became popular, a kelpie was what people originally believed lived in Loch Ness.
Not to mention the only record of a Chimera being killed "led to the unlucky wizard in question falling from his winged horse".note In the original legend, after slaying it while riding the winged horse Pegasus, Bellerophon tried to fly to Mount Olympus (where the gods lived). Guess how well that turned out for him.
The names of the winged horse breeds are taken from the names of mythical horses:
Abraxan and Aethonian: From Abraxus and Aethon, the horses that pulled the chariot of Helios, the Greek sun god.
Granian: from Grani, the steed of Sigurd in the Volsunga Saga, and a descendant of Sleipnir.
Thestral: "Thester", an archaic English word that means, well, dark. So OK not all of them.
The Nundu, which resembles a Leopard — said to be utterly silent, gigantic, and able to wipe out entire villages just by breathing due to the diseases on its breath; it's so dangerous that the only successful kills have come from one hundred wizards working in concert. For comparison, that's ten times as many wizards as it takes to subdue the average dragon.
The Lethifold sneaks up on unsuspecting victims and smothers them in their sleep. And digests them on the spot and leaves no evidence of their demise. They also have a deceptive cunning to boot, that coupled with the fact that they can blend in with a fairly large range of things, means that they could be anywhere.
The Manticore, a Shout-Out to classical Greek Mythology. It has a man's head, a lion's body, and a scorpion's tail, and its sting causes instant death. If that wasn't enough, its skin is nigh-invulnerable to magic. Not to mention it can speak intelligently and croons while it eats its prey. And Hagrid possibly crossbred one.note It's a Rita Skeeter article, so take it with a grain of salt, but if anyone would crossbreed manticores with fire-crabs, it'd be Hagrid.
Then there's the Quintapeds. According to legend they were once a family of wizards before they were transformed into monsters by a rival wizard family, who were in turn eaten by the beasts they created. Whether or not the legend is true, these five-legged carnivorous beasts rate five Xs, and are so dangerous the island they live on has been marked completely hazardous and enchanted so it can't be placed on maps. God help us all if those things are capable of breeding.
Modesty. Is she actually descended from witches and wizards and her wand real? Or was her wand just a toy and she's just a Red Herring?
Graves' relationship with Credence. On one hand, Grindelwald!Graves acts supporting towards Credence and seems upset when MACUSA destroys him, demanding to know who their laws really protect. On the other, he was quick to throw Credence away when he failed him, only showing him care again when Credence reveals he's the Obscurial. Did Grindelwald care about Credence at all or did he only see him as a tool? There is also the question of whether the original Graves knew Credence, and if Grindelwald was building off an existing connection.
Graves seeming sympathetic towards Tina earlier on. Was this just Grindelwald staying in-character as Graves? Or did he see genuine potential (or a possible ally) in Tina, since she assaulted a muggle and had known dislike of the New Salem Philanthropic Society.
Similarly, Graves looked distressed upon ordering the execution of Newt and Tina. Was Grindelwald still caught up in the role of Graves? Did he genuinely regret ordering the death of two young wizards who essentially only got caught up in his schemes by accident? Was he just annoyed at another complication in his plans?
The concept of the Obscurus bears several similarities to the story of Ariana Dumbledore, who also had repressed her magic after a traumatic event and could be downright dangerous if she lost control of her powers. It may also be another reason Grindelwald approached Dumbledore in the first place in order to investigate Ariana.
The very calm, unquestioning executioners. They may have had total trust in Graves' judgement. Alternatively, they might have been placed under the Imperius Curse, as Grindelwald!Graves did not seem worried that they overheard his slip while talking to Newt.
Angst? What Angst?: Both Newt and Tina have very personal reasons for wanting to save Credence. Newt, because Credence is an Obscurial, and the last one Newt tried and failed to save was a little girl. Tina, because she was demoted from auror specifically because she saved Credence from his adopted mother's abuse during one of Mary Lou's sermons, necessitating all No-Majs present to be have their memories wiped. Yet when their attempts to save him are thwarted when President Picquery has Credence killed, Graves shows more anger and regret at his death than either of them.
Possibly justified by shock, and by the fact that Graves seems to have known Credence longer and more closely than either Newt or Tina, to say nothing of Credence's survival being necessary to Graves/Grindlewald's plans.
To some extent, the decision to expand the planned three-film saga into a five-film saga would count. Aside from the most obvious reasons that they'd want to stretch this series out, one of the biggest complaints against the film is that the amount of exposition relative to the amount of action it has wore it down to some degree. Telling a story over a greater number of films, of course, would allow for the story to have more room to breathe while also leaving more room for action sequences. The inclusion of Grindelwald's rise to power makes the decision for several movies even more plausible, as it allows him to be shown as a powerful threat, with people waiting on his duel with Dumbledore in 1945.
The Oblivious Curse is treated here as a pretty terrible thing, which many fans had thought since the original books, especially since it was shown to cause brain damage if done to much, or if badly cast. Jacob's memory being erased at the end is one of the film's saddest scenes.
The base is split as to whether the films are a worthy addition to the Harry Potter canon or a lazy cash-grab.
Several long-time fans have taken issue with the lack of diversity in the casting choices of the main characters, especially since the film is not based on a book. Others have insisted that it isn't really that much of an issue because of the varied background characters in the trailer.
One point of excitement is that we're finally being given an opportunity to see the rest of the world, not bound to the Trio and Voldemort's story. Others have been a little more skeptical, and want the movie to take place in different locations around the world.
One rather sticky point of contention is the announcement that American wizards do not use the term Muggles, instead opting for "No-Maj". Some fans are far too devoted to the word "Muggle" to accept this. Others think that "Muggle" is such a British-sounding word that it makes perfect sense that it wouldn't be used overseas. Still others agree with the latter point but think that "No-Maj" is a weak alternative.
The fact that this is yet another series of prequels following a beloved franchise, especially coming off the heels of both highly divisive trilogies: the Star Wars prequels and the The Hobbit films. Some say that the new movies will follow in the same path as the aforementioned movies while others say to wait and see, as this won't directly tie into the Harry Potter films as much as what the previous prequel trilogies did to their respective franchises. Not helping matters is the fact that the movie has a lower score on Rotten Tomatoes than any of the Harry Potter films, though higher than any of the other aforementioned prequels except Revenge of the Sith.
Johnny Depp's casting as Gellert Grindelwald. A significant chunk of the fandom expressed horror, citing the highly publicized allegations of domestic abuse during his divorce proceedings in 2016note it should be noted that Fantastic Beasts began shooting in 2015, before said allegations were made public. Some (including, apparently J.K. Rowling herself) were happy with the choice and applauded him for being a great actor, regardless of his personal life. More still just think that as an American, he's the wrong fit for a continental European wizard.
Many others felt Colin Farrell's portrayal was vastly better than Depp's Narmy scene, and have set up petitions demanding his return.
Critical Research Failure: Rowling's series of short essays on the history of magic in North America got hit with accusations of this by some fans, who took issue with her interpretations of the Salem witch trials and Native American magic and lore. Others believe it justified by her license to take whatever liberties she wants in her fictional worlds, as well as the fact that they were just short supplementary essays that weren't meant to go very in-depth.
Epileptic Trees: With the revelation that a look will be taken at the rise of Grindelwald, and that he (and presumably Dumbledore as well) will take on a larger role as the series goes on, some fans are pondering whether we might eventually see the famous duel between Dumbledore and Grindelwald for the first time in any medium.
Fanfic Fuel: How Newt acquired the creatures in his care seemes rife with narrative possibilities.
Fashion-Victim Villain: Grindelwald's ridiculous hairdo and makeup do not leave the character with a lot of dignity.
Fridge Horror: To anyone caught up on the Harry Potter books, the origin of the Scourers at first makes no sense, given we were told in an earlier book that the tragedy of the Witch Hunts, from actual wizard perspectives, is that they only killed Muggles, as actual wizards could easily get out of the mess with their magic. To the point mention is made of one Nightmare Fetishist witch who repeatedly got herself caught and burned because she enjoyed the sensation of flames under a Fire-Freezing Spell so much. The realization, and the dawning horror, is that the book was likely referring to the European Witch Hunts, which was purely an outburst of Muggle insanity and callous profiteering (see: the Witch Finder General). In America's Salem Witch Hunts, however, the whole affair was orchestrated by wizards, so those wizards and witches who got caught were probably attacked and rendered helpless by their own people first. Also, no Fire-Freezing Spell is going to save someone who's being hanged, which was the execution method used at Salem Village.
Genius Bonus: The Singer Building that stood until the 1960s in lower Manhattan is the focus of an intro shot, setting the scene nicely for anyone who recognises the long demolished skyscraper.
Jacob and Newt, whose first meeting involves watching an occamy egg hatch together. In the famous suitcase scene, Newt even introduces Jacob to "his" occamy, while referring to himself as their "mummy".
Credence and Graves have more than a few intimate scenes including one where Graves gives Credence a gift and tells him to call on him "whenever he needs him". He is also incredibly handsy with Credence and usually mere inches from him. They also had a deleted scene in which Graves takes Credence to dinner and gives him a flower. The fact that in the books, Grindelwald (who impersonates Graves throughout the movie) was Dumbledore's Closet Key does not help.
It Was His Sled: Johnny Depp's cameo appearance as Grindelwald, which was intended to be a major surprise (albeit one that was hinted at), was spoiled by many outlets a few weeks ahead of the movie's release. Given that his character's presence generated a lot of interest from the fanbase ahead of the movie's release date, and that it directly preceded an increase in opening weekend projections, this might not have been a bad thing. It's actually a downplayed example from the standpoint of the cast and crew, who were afraid that the aforementioned spoiler was going to leak much earlier than it did.
Just Here for Godzilla: A fair number of Harry Potter fans who weren't particularly interested in the premise of a Potter-free movie set in the universe were on the fence about the film got on-board at the last minute once it was confirmed that the film would include a cameo from Grindelwald and would lead up to the legendary confrontation between Dumbledore and Grindelwald.
After Pokémon Go came out, many jokes surfaced about how everyone already knows where to find fantastic beasts. One commenter, Kenny Tee on the San Diego Comic Con trailer even called the film "Fantastic Pokemon and Where to Go Find Them".
Narm: The reveal that Graves is Grindelwald is difficult to take seriously, owing to the character's ridiculous appearance, especially his blonde moustache. His confusing "Will we die, just a little?" line didn't help matters.
Narrowed It Down to the Guy I Recognize: Subverted. Gellert Grindelwald's involvement in the movie's plot was teased, but never confirmed, until the last few trailers, and his actor was kept a complete secret until journalists who attended early press screenings began questioning on social media what Johnny Depp was doing in the movie.
One-Scene Wonder: Johnny Depp's cameo as Grindelwald. The character's presence gives decisive direction for the remaining four films in the series to take.
Signature Scene: The scene where Newt takes Jacob inside his case and shows him his fantastic menagerie of magical beasts.
Squick: Mary Lou making Credence take off his own belt so she can beat him with it, hurting him with his own clothes that he wears at his midsection — she's essentially emasculating him. Graves going the opposite way and trying to bait him with affection and then rejecting him hard for being a Squib and only using him to find the Obscurial didn't do his psyche any favors.
They Changed It So It Sucks: Words in this case, as mentioned above, many fans are upset that the word "Muggle" is replaced by "No-Maj"
With the movie being called Fantastic Beasts and Where to Find Them, you'd think it would be more about, well, the fantastic beasts. While Newt and company catching the beasts does play a part, a large part of the movie is exposition and a subplot that isn't fully explained.
Alternatively, somewhere in the tangle of plots concerning a magical monster loose in New York, Muggles -sorry No-Majs - becoming aware of and hostile to the wizarding world and characters questioning the real reasoning behind the masquerade is a compelling story waiting to be told.
Trapped by Mountain Lions: Almost the entire subplot about the Shaws is irrelevant to the actual plot; it only serves to supply Credence Barebone with an Asshole Victim in the form of Henry Shaw Jr. Langdon helping the Second Salemers or his implied resentment towards his brother, and Henry Sr.'s anger over his son's death end up going nowhere, even when they're explicitly shown outside the subway during the climax as if they're about to do something. Considering their irrelevance and limited screen time, they're surprisingly well-developed, especially when Henry Jr., the only one to be plot relevant in some way, is little more than a Jerkass politician. Perhaps we'll see more of them in the future?
Unintentionally Unsympathetic: Picquery can be a Reasonable Authority Figure, but at times it seems almost as if she is just taking out stress on Tina. This seems especially true at the second meeting scene wherein she sees proof that what is going on might be linked to Tina's emergency yesterday... then proceeds to order Tina to be punished for not telling them sooner when she brushed Tina off.
Catch someone violating the laws? Why, bring them up to the president directly without regards for her being in a meeting. Or better yet, having no security for said meeting to stop her. Although this is mitigated slightly by the fact that the president seems to be in the Auror office for a meeting with Graves, Tina asks to be taken to 'major investigations', rather than directly to the president, and seems surprised to see Picquery herself is there. This is more an unfortunate series of coincidences than anything else.
Woolseyism: In Japan, the film is titled ファンタスティック・ビーストと魔法使いの旅 (roughly Fantastic Beasts and the Wizard's Journey), following the naming structure of the Potter books and helping to show that this is a new adventure taking place in the same universe. Additionally, the bottom of the kana character ビ is elongated into an occamy's tail much like the S in Beasts in the English logo.