Ascended Fanon: In Tinker's Seal, Star Shimmer is implied to be related to a mythical dark lord from the north, referring to the legend of the land of Ultima Mule. However, with the return of the Crystal Empire, scholars theorized that the legend of Ultima Mule was in turn based on the Crystal Empire. When the author was asked if her ancestor was King Sombra, the author decided to go with it.
Goa Trance duo, Genom Screams and Sweet Psy, are big fans of the series, and made some fan music for it around the time Breathing Weapons was being written. Come the companion-soundtrack release of book, the author deemed the songs 'excellent' and had them included on the album as bonus tracks.
For the most part, Ember Roundup was happy with Amber of the Smooze, but admitted using Gusty Lulamoon's younger cousin as inspiration for Princess Sparkler without asking permission and exaggerating some of her negative traits to outright insulting levels, all the while profiting off the caricature, wasn't exactly one of her proudest moments. This was originally revealed in a Gabby Gums article, whose photographer discovered several unsent, rewritten apology letters. Ember would later give a more complete explanation in The Fillydelphia Tribune. The Tribune article would further elaborate that as an apology, not only would Ember donate royalties to said cousin, she intends to include her as a creative consultant in the upcoming Alicorn Amulet.
Kevin J. Canterson rarely gets fan mail for Buffalo Burial Grounds. When he does, he's been rumored to write back and ask for hate mail instead.
Annon N.E. Moose was apparently disgusted with Rail's portrayal in fanfiction as a puppyphile rapist. True, his relationship with Shudder was definitely inappropriate, but still a loving one.
Ember Roundup, following the death of Gusty Lulamoon and her discovery that Beatrix Lulamoon had fallen off the map during the last two years. While her work on Tinker's Seal didn't suffer, she did pull out of a planned collaborative project with Steeplechase Moffat, giving him permission to finish off the Colt of the Smooze arc, and concentrated on her work for the Tribune for several months. Thankfully, her friendship with Beatrix has done a lot to revive her passion for the series.
As the Blood Diamonds series gets darker and more depressing with each installment, people suspect Ghost Writer is suffering from something.
It was recently confirmed that Rachael Neigh Cook would be voicing Eichelhäher in the upcoming Breathing Weapons animated mini-series.
Hossed: There was speculation that Princess Sparkler's first name, Twinlight, was based on Princess Twilight Sparkle after her name was revealed in some of the previews of Alicorn Amulet. Though claimed to be a complete coincidence at first, when pressed the author stated the name was always intended to be Twinlight, and the name was actually based on Twilight Velvet, fellow adventure novel author and Twilight Sparkle's mother, who Ember interviewed in her early days at the Fillydelphia Tribune and considers a mentor.
On that note, the "newcomer" co-author of Alicorn Amulet was for several months rumored to be fanfic author MagicSpark, due to other unconfirmed rumors of her real identity being at the centre of the Alicorn Amulet incident in Ponyville. This was hossed first by a blog post from her revealing that certain responsibilities would be keeping her away from writing for a while, and again by the announcement of said newcomer being named A. Sparkler Star. Neither of these announcements have done much to end the speculation along these lines, though the above-mentioned revelations about Twilight Velvet have pushed much of the fanbase to adjust their theories.
A rumour that conspicuously hasn't been hossed, despite reaching Epileptic Tree levels, is of A. Sparkler Star being a teenage Ponyville resident by the name Sparkler. This is largely based on her being an eyewitness to Lulamoon's reign in Ponyville, and also Muffin Parcels' adopted daughter, regardless of the fact that she has no direct connection to Roundup or the Lulamoon family.
Old Shame: The wildly unpopular Mareval Comic series for creator Alan Moooore.
Buffalo Burial Ground is this for Kevin J. Canterson.
One of Us: Princess Celestia herself has admitted to enjoying the series, and introduced Princess Luna to it upon her return. The latter was also reportedly very excited to meet Ian McCloppen on the set of Legacy of Nightmare Moon.
Reclusive Artist: The author of the original Daring Do books, to the point that nopony even knows his/her name, or if it was the work of a single pony/non-pony. There's a rumor that Twilight Velvet, mother of Princess Twilight Sparkle and the Crystal Empire's Prince Shining Armor, is the author.
One of the artists featured on the Breathing Weapons soundtrack goes by the name of, "Satellite Rock". A quick internet search shows this to be the only song by an artist of that name. Given the style of the song, it's widely speculated that the song belongs to the DJ Duo, Blendit/Mixit, but it's still unconfirmed.
Too Soon: Many had this reaction to the description in Purloined Stone of what Discord did to Daring et al.
Similarly, Daring Do and the Cloudfall Conspiracy was first envisioned as a crossover with the Con Mane franchise, but legal and financial issues with the latter's copyright holder prohibited this from happening.
Breathing Weapons was originally intended to be a full spin-off centered around Daring in her later years, her having retired from exploring jungles and ruins and instead doing police work for Celestia. During draft stages, it was deemed too far a departure from the series, and was instead turned into the more traditional (though still quite different) book we have now.
Gospel also claims there was going to be another Greifvogel member by the name of, "Adler", but he was cut because, "there were enough griffons as it was".
Breathing Weapons got released in some regions as, Daring Do and the Industrial Heart for unknown reasons.
In the first few drafts for Iron Grinder, Goblin Grave was originally going to take up Jackhammer's offer to marry Shudder in exchange of giving up his position as pack leader, but Moose realized this would most likely lead to some pretty creepy assumptions by the fans, and as a result, this scene was cut.
There are rumors floating around that the scene where Jackhammer beats Shudder was originally intended to have heavy implications that he had raped her as well, but the writer hasn't said a word about it. Though, recently, a lot of people are claiming this is a rumor started to combat the common portrayal of Rail as a rapist in fanfiction.
The plot of Gunpowder Groove was originally a heavy, realistic take on Zebra racism, with Daring actually casually throwing around the word, "Zigger". Voyage's editor deemed it too serious a topic to tackle, and it was rewritten as a more light-hearted adventure story. Voyage later admitted that this was most likely for the better. Plus, given that Daring's friends with Okpono, who is a zebra, her throwing around language like that would be uncharacteristic.
Gospel claimed she wanted to do a story based on Arzt and his parents finding him after his defection, but her publisher wouldn't allow it due to the fact that it was a Daring Do story that didn't even feature it's main protagonist, and Arzt wasn't as established a character like with the Daren Do Adventures and the Tales of the War series, and was too big for a short story.
Gospel has recently stated that this idea will be explored in the upcoming Globetrotters spin-off.
Some of the early drafts of Amber of the Smooze had the Colt Leader be a Jekhoof and Hide personality of Desert Rose caused by Smooze contac, or an Enemy Without named Tresed. The Colt Leader was later re-imagined as Desert Rose's Bizarro Universe alternate.
What the Hell, Casting Agency?: In the new trailer for the latest adaptation of Alicorn's Shadow, Haystack Leaves has been revealed to play Mareton. Although the stallion's a perfectly good actor, the reaction of many fans was simply, "What." Whether or not he can pull off playing a villain remains to be seen.
Now that another trailer has been released, the general reaction was: "Oh. Right then. Carry on."