Liev Schreiber accepted the role of the film's main antagonist, the Storm King, because he was eager to appear in a film he would be able to take his children to see, noting his repertoire of violent, adult-oriented films.

This is the first feature length "My Little Pony: Friendship is Magic" film that is not part of the "Equestria Girls" series.

Kristin Chenoweth had input in choosing the color of her character's mane.

The name "Celaeno" originates from Greek mythology, belonging to one of the Harpies (bird-like creatures).

Liev Schreiber considers the Storm King to be "one of the more intense roles [he's] played".

Michael Peña ad-libbed much of the character's dialogue, with Meghan McCarthy saying, "You get Michael Peña in a recording booth, and you just are like, 'Please just go and say funny things.' He will be there for hours, just giving you all kinds of really great material that was not something that we had originally scripted!"

Fan favorite characters the Cutie Mark Crusaders (Applebloom, Scootaloo and Sweetie Belle) appear in non-speaking cameos. Despite not having any lines, Michelle Creber got listed in the credits.

This is the second "My Little Pony" theatrical film in the saga's history, after My Little Pony: The Movie (1986).

The Seaponies in the film are inspired by the mythological creatures known as hippo-campuses, which were typically depicted as having the upper body of a horse and the lower body of a fish.

Discord makes a brief appearance in the film as a balloon animal Pinkie Pie makes.

During the music panel for BABSCon 2015 in San Francisco, Daniel Ingram suggested the possibility of working with a live orchestra on the film's musical score.

Songbird Serenade's design is modeled to reflect her voice actor Sia's stage persona, complete with large wigs.

Kristin Chenoweth said that she dabbled in method acting for the role, making sure her hair was "on point for every recording session".

Most of the heavily mixed reviews that the film received from critics were particularly based off of it being made from a toy line rather than actually reviewing the story and screenplay, direction, animation, characters, performances of the cast, and music. This has been criticized by audiences as being an example of critics not going deep enough in their reviews, being too prejudiced and stereotypical of certain franchises, and once again not being in the same league as audiences. Another example from 2017 is Pirates of the Caribbean: Dead Men Tell No Tales (2017), in which the surveys that many critics made were not criticizing only the film, but were making vague retrospects on the series as a whole instead.

Liev Schreiber accepted his role as the Storm King due to having a lack of family-friendly roles in his career.

This is only the 3rd theatrically released traditionally animated American film of the 2010s, after Winnie the Pooh (2011) and The SpongeBob Movie: Sponge Out of Water (2015).

Meghan McCarthy noted that Emily Blunt's performance was "a big influence" on how Tempest Shadow was animated in the film.

Meghan McCarthy stated that as the film's villainous comic relief, Grubber "needed to be goofy" to counterpoint the "very straight-laced, hard core [sic]" Tempest.

Tempest doesn't have a cutie mark shown, but The Storm King symbol on her armor is on the spot where one could be.

On the development of the character, screenwriter Meghan McCarthy said, "We just arrived at this idea of a character who had come from Equestria, and had not had the positive experience that Twilight [Sparkle] and her friends had. It felt like a good counterpart to our heroes was to have a villain who didn't just not get friendship, but had a reason that she didn't understand it."

Uzo Aduba voices Queen Novo, the mother of Kristen Chenoweth's character Princess Skystar. In actuality, Aduba is 13 years younger than Chenoweth.

Both the 1986 and 2017 films have a scene where a pony falls over a waterfall.

While the initial returns were considered poor from some sites, Cartoon Brew's Amidi stated that since Lionsgate is not directly in the business of releasing family-friendly films, the opening take readily exceeded the distributor's other attempts at this genre; likewise, Amidi estimated that the film had a budget between $5 to $8 million, based on budgets for films with similar styles as well as accounting for the work being done primarily in-house at Hasbro to reduce costs.

Capper references The Wizard of Oz (1939) by saying what about the queen of lions or tigers or bears? Followed by a pony saying "oh my!"

Kristin Chenoweth and Uzo Aduba, the voice actresses to Princess Skystar and Queen Novo, have both played Glinda the Good Witch in productions of The Wizard of Oz. Kristin originated the role of Glinda in the original Broadway Cast of the long running show "Wicked". Uzo played Glinda in "The Wiz Live!".

At the beginning of the movie, "We Got the Beat" by the Go-Gos is playing, but the lyrics are changed to fit in with Equestria.

Adam Bengis had been fighting leukemia for over 3 years when, through the Make A Wish Foundation, got to fulfill his dream for voice acting in the film. He plays an extra pony named Code Red and is listed 3rd in the closing credits due to the credits being alphabetized by last name. His lines include: "Is that Songbird Serenade? It is! It is!" and "Way ta go guys!"

When Grubber first arrives and sets up his announcement system, as the speaker extends it makes the iconic Transformers transforming sound. Hasbro owns both the My Little Pony and Transformers properties.

While on the beach, just after the first attack, the Mane 6 and Spike are discussing hippos. Pinkie Pie says that they are always "hungry." Spike repeats "hungry?" And Applejack asks "hippos?" "Hungry Hungry Hippos" is a board game owned by Hasbro, which also owns My Little Pony.

Songbird Serenade's bodyguard's are a nod to Vincent Vega and Jules Winnfield (John Travolta and Samuel L. Jackson, respectively) from Pulp Fiction.

This is the second animated movie of 2017 to be based off a children's TV series. The first was The LEGO Ninjago Movie (2017), which released 2 weeks before this movie.

This is only one of the 4 theatrically released traditionally animated films of the 2010s to not have any humans, of which were featured in Winnie the Pooh (2011), The SpongeBob Movie: Sponge Out of Water (2015) (in live action form though) and Teen Titans Go! To the Movies (2018).

3rd PG movie for Andrea Libman. Her first 2 were Andre (Paramount Pictures) and Little Women (Columbia Pictures), both released in 1994.

Michael Pena's 4th Animated Film, after Turbo (2013), Hell and Back (2015), and The LEGO Ninjago Movie (2017).

The end credits are done to the style of Tempest's flashback, which was in turn an homage to an art style that pops up in the series often, specifically when someone is fantasizing.

The major presence of the Seaponies is an homage to My Little Pony (1984), where the Seaponies appeared and gave crucial help to the Ponies.

In the movie, the Storm King holds "The Staff of Sacanas". Sacana is a Portuguese word that translates to rogue/trickster, meaning the staff is the staff of rogues/tricksters.

The Storm King's death marks the 2nd villain killed off in the My Little Pony series (following King Sombra's death in the Season 3 premiere), though it was by his own hand.

The film's hero (Twilight Sparkle) and villain (Tempest Shadow) both share the initials "TS". But she at the end of the movie reveals her real name is Fizzlepop Berrytwist.