Q&A
Q: How was he assigned to write the episode?
A: The episode was already being written, but a scheduling derp made him switch over to Slice of Life instead of Lost Treasures of Griffonstone
Q: How were background characters picked?
A: Amy Keating Rogers came up with the idea for the Cranky wedding. Before that, it was just titled "Tour of Ponyville" without any structure, with Twilight showing someone around and running into characters.
Q: How much longer did the episode take?
A: A lot longer. He had to read all of the season 4 scripts to look for characters, rewatch all the older episodes for interesting backgorund ponies, and sneak them in somehow. There was a lot of research that went into writing it. Insane and fun was the goal
Q: Will the characters talk in future seasons?
A: Maybe.
Q: What allowed Derpy this time around?
A: Her name is muffins officially. Even though Larson originally called her Derpy for the sake of labeling in the script, Hasbro had him switch the name even if it was never actually said in the episode.
Q: Was there ever a moment where they considered adding Applejack as a joke?
A: Noo
Cut Scenes
In the first draft Vinyl Scratch's talked, but they told him she doesn't talk, so it was removed in phase 2.
The original Vinyl Scratch and Octavia scene involved Vinyl crashing at Octavia's house and destroying her sofa. So she goes to Quills and Sofas to buy a new one. They weren't originally roommates, but The Hub and Hasbro made them roommates.
Flash Sentry was originally in the script. He was following Cranky asking why no one likes him.
Another cut scene was a group of ponies coming in, and a group of their recolor ponies running into them, followed by awkwardness.
His original reason for not wanting to bowl, was because he had trauma as a kid where he couldn't figure out the physics behind it, which lead to his science focused career.
Sombra appears in front of Octavia, and a "Devil went down to Georgia" song battle starts up.
Outside of episode 100, there was originally a cut scene where after Twilight is coronated, Rainbow Dash and her fly around Equestria, eventually ending up in dragonland where they do a musical scene.
There was a scene where Derpy is saying "I don't know what to do doc! I don't know what to do!" and the camera pans over to reveal Dr. Caballeron, revealing Derpy at the wrong table with the wrong doctor. Gags like this were throughout the entire original script.
After everyone is gone and in the town hall, the bat ponies and royal guards are outside doing silly impressions of Princess Luna and Celestia. "Every day shall be cake day!".
At one point, Lyra tells Bonbon to "stop using that ridiculous voice!" to make fun of her other voices.
In the script, Gummy had a french accent.
There was a moment where Doctor Whooves is running up to Carousel Boutique, and he sees Opal and Tom.
A scene between Coco Pommel and the pony from season one in Boast Busters with the green mane that Rarity accidently insults was cut. She had a full green wedding ensemble on with Coco's stamp of approval, and said she couldn't wait until Rarity saw it as revenge. Coco Pommel then says she doesn't really like green, and asks for anything in pink.
The original ending had the hugging scene with the mane 6 being their usual end-of-episode corny selves, but the camera pans to the sunset where a changeling army is flying in...
General Interesting Things
M.A. Larson originally didn't want to do the episode. The characters had no specific canon so he wasn't sure what to do. Eventually they just decided to "Go for it" and make it a Brony episode. This episode wouldn't exist without us, and our background pony fanon.
His outline list was 10 pages long with all the characters.
Hasbro/The Hub was the original driver for this. M.A. Larson kept telling them it was a bad idea, but they kept pushing it. An "Alt mane 6" episode. He eventually figured out it was fun, and sent a note to Hasbro saying "Add more pandering!" It's not a normal episode
Hasbro told him to turn the bugbear into a panda style.
The whole Lyra and Bonbon scene was a "True Lies" reference.