Spoiler:
List of humanized ponies from when I first spotted them:
- The night watchman looks to be the same one from It's About Time (S02E20)
- [out of universe] 30 moons... or about two and a half years. A nod to the two and a half seasons of the show, maybe.
- The portal as a concept isn't too dissimilar to the mirror pool in Too Many Pinkie Pies (S03E03). Pinkie Pie mentions a "twin" of Twilight not yet seen.
- Furthermore, the point that the human Twilight is in another city with this universe's Spike while the rest of the main cast already know each other is a parallel to the beginning of the series.
- Fluttershy's introduction to Twilight is basically a straight copy of the same from Friendship is Magic, part 1 (S01E01) - Applejack has a similar parallel in catering, as does Rarity in immediately giving Twilight a new outfit.
- Big Mac is still concise in his speech.
- The Cutie Mark Crusaders are listening to their song from The Show Stoppers (S01E18) and get a similar takeaway from the results.
- Twilight is used to sleeping in a library, of course.
- The yearbook photo is basically the same as the one sent to Celestia at the end of the opening credits (minus Twilight).
- Rarity still finds Spike to be very cute, as in Secret of My Excess (S02E10) and other episodes. It's more of an expected reaction in the human world though.
- Wonderbolts to Wondercolts, pretty straightforward analogue.
- Pinkie Pie wishes for her party cannon that's shown up in Sweet and Elite (S02E09) in addition to a few other episodes.
- Fluttershy's "yay" returns when everyone puts their hands in before the cleanup.
- Rarity has put Rainbow Dash in a frilly dress before when Celestia came to visit in Swarm of the Century (S01E10)
- Pinkie's hair poofs back after straightened as in The Best Night Ever (S01E26)
- Spike's predilection for mustaches goes back to Boast Busters (S01E06)
- Scootaloo does the chicken dance, a nod to Apple Bloom calling her a chicken in The Stare Master (S01E17)
- Rainbow Dash's "So awesome!" is back from Applebuck Season (S01E04)
- Sunset Shimmer's transformation and altered voice kinda resemble that of Chrysalis in A Canterlot Wedding, part 2 (S02E26)
- The Elements of Harmony work their rainbow of destruction as they did in Friendship is Magic, part 2 (S01E02) and The Return of Harmony, part 2 (S02E02)
- Scootaloo didn't even know she wanted to fly but got a ride from Rainbow Dash as she did in Sleepless in Ponyville (S03E06)
- Twilight's dancing hasn't improved since her birthday party in Sweet and Elite (S02E09)
- Diamond Tiara and Silver Spoon still have their "Bump, bump, sugar lump rump" dance from Call of the Cutie (S01E12)
- Derpy's love of muffins returns again in the credits after becoming an ascended meme from Applebuck Season (S01E04)
- Diamond Tiara and Silver Spoon bump into Twilight in the first crowd scene while Cloud Kicker passes the other direction. Possibly Carrot Top, Rose, and Cherry Jubilee too?
- Cheerilee, Vinyl Scratch, Photo Finish, and the Cutie Mark Crusaders in the first song.
- Granny Smith as a lunch lady in the cafeteria, Trixie and Twist at different tables.
- Snips and Snails make good henchmen, as usual.
- Derpy shows up in the corner of the screen during the song in the cafeteria.
- A couple of Rainbow Dash's bullies show up as jocks in the background.
- Mr. and Mrs. Cake again in charge of a sweet shop.
- Doctor Hooves appears in yet another incarnation during the mind control scene.
Aparte de ello, parece que a alguien en la producción de EG le gusta Lucky Star: