Keroro often speaks Spanish or embodies various Hispanic stereotypes due to his voice actor Yoshi being Dominican.
In Episode 2, Aki mentions that the guy who removed the ghost from the basement was "some guy from Florida", a reference to Kululu's voice actor, InfamousGentleman, a then-resident of Florida.
In Episode 21, Keroro says he failed Biology, which happened to Yoshi in real life.
Ascended Fanon: Of the premeditative variety. When the counter debuted in Episode 13, viewers calculated that, if it counted down in real-time, it would reach 0 on April 23, 2012. The writers made it so that Episode 16, wherein the counter activates, would correlate with that date, though because Keroro makes the counter activate a week early, the episode was uploaded a week earlier as well.
The Cast Showoff: LillyLivers sang as Natsumi for the 2010 Christmas Special and as the gender-ambiguous Sumomo in Episode 8, and she can sing.
The creators openly disowned the original Episodes 1 and 2. They remade them to make them funnier, more in-line with their current writing style, and in-canon with the current continuity. Subverted with Episode 3, which was only remade due to the plotholes and dead references that resulted from the first two remakes, as otherwise Thorn and Yoshi don't consider it a bad episode.
Thorn is fairly unhappy with Episode 8, and he, Yoshi and Travis consider Episode 13 to be their worst.
Yoshi also included Episodes 4 and 6 as favorites on the podcast: 4 primarily for when Dororo shows up, and 6 because he had wanted to parody the radio episode(s) since the early planning of the series, and it ultimately came out even better than he had hoped. Thorn largely agrees with him.
Averted for most of the characters, though Tamama is a weird example. She starts out being considered male and therefore an aversion in Season 1, unlike both the Japanese and Funimation versions of the original series, until she is revealed to be a girl in Episode 10, becoming a subverted example and a complete inversion of the original's crossdressing voice.
Young male characters Private Taruru and Gyororo are voiced by female VA LillyLivers.
Directed by Cast Member: The series' voice actors are directed by Thorn, who also voices a large chunk of the cast.
For a time, Thorn kept forgetting that Tamama was male and not female. He randomly came up with a joke that would reveal that Tamama really was a girl, and he and Yoshi decided to make it canon. After deciding this, they would occasionally make unintentional Freudian slips revealing this secret, but they simply pretended that they were still confused about Tamama's gender. Then Episode 10 rolls around...
Meaningful Release Date: Episode 16 was released on April 16, 2012. When the Kiruru counter appeared in Episode 13, viewers calculated that, if it counted down in real-time, it would activate on April 23. Because Episode 16 starts with Keroro activating it seven days early, the episode was uploaded a week earlier as well.
There were several voice actor change-ups during the original first five episodes. These were all retconned out of the series with the Episodes 1-3 remakes, and the cast change was one of the reasons why they were remade. There were also numerous voice actors brought in to voice Dororo, Momoka, Omiyo, Natsumi, and Paul but were replaced before they ever appeared in an episode.
Thorn voiced HQ in Episode 1R, but when HQ returned in Episode 10, he gave the voice to team friend Jiggly Jacob.
Giroro was voiced by DFatman at the end of Episode 1R. Thorn stepped in as backup should Fatman be unable to record, but Yoshi preferred Thorn's voice anyway, so he became the permanent voice shortly before Fatman was kicked from the team.
Kululu was voiced in Episodes 2R and 3R by GhostTC, who dropped out of the series before Episode 4. InfamousGentleman voiced Kululu from Episode 5 on.
Mois was voiced in Episode 2R by RenegadeFaith, but she was replaced with codeblackhayate in Episode 5.
Momoka was voiced in Episode 2R by LillyLivers as backup after four months of failing to find a stable voice actor and delaying of Episode 2R (Thorn also filled in as Momoka for an episode trailer). The team were so frustrated with Momoka that she was left out of Season 1 until Episode 10 out of spite. From then-on she was voiced by Dobuchu.
There was supposed to be a running joke involving Thorn and Yoshi trading off each episode as the voice of Tamama, as evidenced by early team podcasts, but Yoshi only voiced the character in Episode 3R before losing the voice and retiring as the character. It was one of the reasons that Episode 3 was remade despite being a mostly competent episode.
ShazMyBot from Gutted Wren Studios voiced Dokuku for Episode 20, but by Episode 21 he had stopped voice acting, so Jiggly Jacob took over as Dokuku.
Revy Moonshine, also from Gutted Wren, voiced Koyuki from Episode 4 to Episode 18 before stepping down prior to Episode 22. Thaichestnuts filled the role from then on.
Ches also filled in for Teddy as the voice of Nuii from Episode 22-24.
ThePS2Godnote now TheOneManBoxOffice, the original voice of Momoka, Omiyo and Dororo, had recorded lines for Episode 2R before being kicked from the project. However the then-script ended up not fitting with the source video, so his recordings were scrapped.
Al Vee, one of the voice actors for Momoka during the character's SFA2R fiasco, was the only VA before LillyLivers to record lines with the finalized script. Al's health and living situation prevented her from finishing recording, and after a failed attempt to find an understudy for Al, Lilly was asked to voice Momoka as backup.
Teddy, a young friend and fanboy of the team, was made official team artist in December 2011 and drew the artwork that made up Giroro & Dororo's wedding in Episode 15, the official SFA logo from Season 3 onward, and various other contributions.
Prop Recycling: Still frames and footage from older episodes were reused for the Episode 10 Dollar Store scene, the season finale cast roll calls, and for SFA: Reset, either for the character models or the settings.
Reality Subtext: Subversion. Writer Thorn came out during production of Episode 11 as a bisexual transvestitenote he has since stated he is Pansexual and Genderfluid, but he states that he has always been an LGBT activist, so the series' examinations of sexuality were likely to happen anyway.
Schedule Slip: Episodes 4 through 15 were released one-to-two months after each other. After Episode 15, there were often several months between new episodes, due on two occasions to the canceling and uncanceling of the series, with Episodes 20 and 21 being a whole year apart from each other. Thorn intended to do an episode a month again following SFA21 through to the season finale, but that too slipped when SFA22 took longer to figure out than he'd hoped.
Shipper on Deck: The reason Giroro and Dororo were made a couple is because Thorn ships them.
Lil' Keroro's over-the-top la-la-laing in Episode 4 was just Yoshi goofing off during recording. Thorn wanted to keep it, and it was even brought back in Episode 7.
Lil' Keroro's shocked expression in Episode 4 is simply a frame of him turning his head that Yoshi discovered by accident.
Keroro brushing his toothbrush in the Episode 2 Post-Credits was a result of Yoshi mistyping "I'm going to brush my teeth" as "I'm going to brush brush my toothbrush" during scriptwriting for SFA2R. Thorn liked the idea of Keroro brushing his toothbrush, so it stayed. It was shortened for 2R, but the entire line was later put into the remake.
Keroro's comments to Dororo at the end of Episode 14 - about remembering his name and giving a high-five - were ad libs by Yoshi.
Keroro trips over himself trying to say a tongue twister in Episode 16. Yoshi was supposed to play the line like this, but the take used was him tripping over his tongue for real.
Keroro asking "Is it off?" at the end of Episode 17 was an ad lib by Yoshi.
Travis jokingly did a parody of the THX crescendo while doing the monster powering-up yell in Episode 18. This ended up being the take Thorn used in the episode.
The middle third of Revolver Ocelot's closing lines in Episode 24 was a flub by Jacob. Thorn decided to put it into the episode rather than save it for the gag reel.
Trolling Creator: While the series does away with nearly all of the tropes and iconic elements of the original anime within the first several episodes, Thorn and Yoshi still slipped in a tongue-in-cheek conversation in Episode 5 about Gundam models and SFA-Keroro's apathy towards them. This was an intentional laugh at the expense of their audience, since a large portion of their fans were also fans of the original series, and a key part of the original Keroro's character is his love of Gundam models.
Un-Canceled: Originally ended after Season 2 in November 2012, with the creators seeming prepared to never look back. Three months and a failed attempt to start another Abridged Series later, Thorn was more than happy to bring it back and do it again for one more season.
There was talk briefly during the series' early days of it becoming part of WingerDinger Productions, due to LillyLivers' involvement in the project. This was shortly before WingerDinger was hacked and subsequently abandoned, so nothing became of it.
Momoka's death in Episode 13 was simply a joke, and they would have brought her back the next time she appeared in an episode. However her voice actress Dobuchu moved to Japan around the time of Episode 14. As a result, they simply left her dead. Dobuchu returned to the US in 2013, allowing Momoka to return, but she wasn't revived until Episode 22 in August 2015, and she did not appear in either of the series' remaining three episodes except for the series finale cast roll call.
The climax to Episode 10 with Future Kululu is what happens when Thorn takes numerous disparate elements from the first season and tries to tie them together. He and Yoshi barely planned for the climax prior to scriptwriting, despite Episode 10 having the most planning of any episode up to that point.
Viper only became Dororo's father when Yoshi joked about Viper's eyepatch being similar to Lil' Zeroro's mask, and that Zeroro's mask was a hand-me-down eyepatch. They ran with the fatherhood joke, and by Season 2 Viper's Big Screwed-Up Family was a recurring plot point and a key theme of the series.
The intention for Keroro's monologue in Episode 18 was for him to blame his parents for all the troubles in his life. After two minutes of the writers thinking about what could apply to that, it turned into a reveal that Keroro is Dororo's little brother.
Yoshi never intended to be a voice actor, let alone the voice of the main character; he just wanted to script-write and oversee the project. While he didn't quite like voice acting during the first three episodes, he began enjoying it starting with Episode 4, and it became one of his main hobbies after stepping down as SFA's writer.
Thorn believes that the series is one of the behind-the-scenes pioneers of live voice acting direction in abridging. Starting in mid-2010, Thorn began directing the voice actors over Skype to speed up the process, thereby allowing him to get the takes he wants outright and avoiding the need to re-record lines should they not work with the source video. Many of the long-established and prolific cast members (E.G.: LillyLivers, codeblackhayate) note that SFA was one of their first online voice acting roles with live direction - most online amateur voice acting is done alone and impersonally, relying on directions from the script or project heads, and is often a long-running process of sending in lines, waiting, and re-recording lines later. From 2011 on, many abridgers adopted live directing themselves, and it is now a common practice, though solo recording is also still common.
Thorn admits that he wanted to run the project and voice practically everyone in the formative, circa-SFA1R days. Fast-forward to 2013, and he does run the project and voice a majority of the cast.