Brought to us by the same author who gave us Lelouch of the Second Chance (recommended above), this fic is a surprisingly well-written crossover between Code Geass and one of Zero's more obvious inspirations, Kamen Rider. The plot seems to borrow a few ideas from the Manga adaptations of Code Geass, such as the lack of Knightmare Frames, Japanese students already being enrolled at Ashford Academy (both taken from the Code Geass Manga), Lloyd meeting Suzaku at the Academy (inspired by Suzaku of the Counterattack) and a more heavily armoured Zero (inspired by Nightmare Of Nunnally). Notably, it's revealed early-on that Zero is not Lelouch, rather, C.C. is (again, inspired by Nightmare Of Nunnally, where C.C. was the source of the Zero Armour and could also take that form). Lelouch ends up gaining his own unique armour a few chapters in, however. Much like some of the Nasuverse crossovers recommended above, it is possible to read this fic with little-to-no knowledge of Kamen Rider, and still thoroughly enjoy it. Be warned that the story itself hasn't updated in a year. However, the same could be said of kyugan's other fic, which has received the occasional update, so both fics still could be alive.
FanficRecs Little Serge's review
Brought to us by the same author who gave us Lelouch of the Second Chance (recommended above), this fic is a surprisingly well-written crossover between Code Geass and one of Zero's more obvious inspirations, Kamen Rider. The plot seems to borrow a few ideas from the Manga adaptations of Code Geass, such as the lack of Knightmare Frames, Japanese students already being enrolled at Ashford Academy (both taken from the Code Geass Manga), Lloyd meeting Suzaku at the Academy (inspired by Suzaku of the Counterattack) and a more heavily armoured Zero (inspired by Nightmare Of Nunnally). Notably, it's revealed early-on that Zero is not Lelouch, rather, C.C. is (again, inspired by Nightmare Of Nunnally, where C.C. was the source of the Zero Armour and could also take that form). Lelouch ends up gaining his own unique armour a few chapters in, however. Much like some of the Nasuverse crossovers recommended above, it is possible to read this fic with little-to-no knowledge of Kamen Rider, and still thoroughly enjoy it. Be warned that the story itself hasn't updated in a year. However, the same could be said of kyugan's other fic, which has received the occasional update, so both fics still could be alive.