Banned In China: China specifically for: A) Portraying the Chinese as manipulative eunuchs, B) exemplifying the dignity of conquered peoples going hand-in-hand with striking back against the government, and C) having Tibet as an independent nation (reference is made to the Tibet Convention).
Fan Nickname: Many. For example we have Spinzaku, Pizza Butt, and Emperor Wakamoto.
Also, fans have a tendency to nickname a character done by Jun Fukuyama or Johnny Yong Bosch into something related to Lelouch or Zero.
Gwendolyn wants you to know what this badass mother can do!
And don't forget our Empress Tianzi. If she wants it, she could have sent four crazy Oni and a time-travelling Kamen Rider to help in the rebellion. And punch anyone hard.
Popularity Redo: The second season was completely reworked because, being very popular, it was moved from the midnight slot to a much more mainstream time, and a lot of the edgy stuff had to be removed. This is arguably the main reason why R2 had such hectic pacing.
Word of Dante: Many fans believe that Lamperouge was Marianne's maiden name, despite the fact that she's only ever referred to as "Marianne vi Britannia", even in media depicting her pre-marriage (such as the novel where a teenage Marianne helps prevent one of Charles' uncles from taking over the throne).
While we're on the subject of Code Geass and WTF, consider the third Alternate Continuity manga Nightmare of Nunnally. It turns Nunnally, the anime's woobie, into a psychic Little Miss Badass with an Evangelion clone who fights evil, and has Lelouch and C.C. merge into a demonic-looking Zero who fights Knightmares on foot in a fashion that would do Master Asia proud. These are the least strange things in it.
NON is nothing compared to the fourth manga Strange Tales of the Bakamatsu, which puts Lelouch as head of the Shinsengumi and the Black revolutionaries, which are really the same thing. Also Geass is the power to summon Knightmares. Oh and Britannia sent the Black Ships of course. Then there's the second manga, where there are no knightmares, and Lloyd gives Suzaku a power suit that lets him become the government sponsored superhero Lancelot.
The main series manages to outdo both of those during its second season when the protagonist kills his immortal dad by mind-controlling God.
All of the above are blown away by most of the parody sound episodes, the High School AU one in particular. To give a general idea, Lelouch is a new teacher, and pretty much everyone else is the head delinquent. Cecil beats Cornelia and her battle yo-yos and Charles is the 98th Holy Britannian Head Delinquent who erases Lelouch's memory at the end for no real reason whatsoever.
And yet actually ridiculous stuff like making a giant pizza goes unmentioned. No, wait, failing to make a giant pizza twice, because of a klutzy dough-spinning mech and because Lelouch shoved C.C. into the tomato sauce, respectively.
Don't forget the pure insanity that is The Love Festival. You start to wonder why Milly uses the entire school just to annoy her Vice President.
One of the main character's motivations is avenging the murder of his mother and discovering who was responsible. In the end, who killed her? He did! What was the murder weapon? God.
The fact that this was made possible by his mother body-swapping herself into a conveniently positioned bystander, which she had to do because an immortal androgynous midget had machine-gunned her to death, makes this even sillier.
Well, when spoilers came out early to midway through R2 with regards to some of the later episodes - especially those about Suzaku using FLEIA to blow up Tokyo in episode 18 and the the Black Knights betraying Zero in episode 19 - most people thought that they were totally crazy and that there was no way that they could be true. But, lo and behold, they did happen. And of course there are fans that still think that it's crazy that they happened even after seeing why they happened.