This is the first mainline Shin Megami Tensei game not to feature moon phases or some variation thereof.
Bad Export for You: The game's European release came well over a year after the Japanese and North American ones. It was in English only, in contrast to the standard of European-release games being available in multiple languages, and was available only for digital download, unlike the Japanese and North American releases which are both available in physical form as well.
Troubled Production: While a more subdued case than most, the game suffered from the new and old members of Team Maniacs having different ideas of what to do with the game causing a drift between them, with the old guard wanting to stick to series standards while the new wanted to input things they where accustomed to such as "sweet" female characters and various classic anime tropes.
The standard Samurai uniforms used to be gray and black until they decided that it wouldn't make sense for the Black Samurai to be considered conspicuous if all Samurai wore dark uniforms so they switched over to blue and white.
Lucifer Palace and Purgatorium were originally the final dungeons for the opposite alignment route, Lucifer Palace for the Chaos route and Purgatorium for the Law route, they were switched for symbolism.
An idea that went unused for Lucifer Palace was Lucifer's eye being seen in windows, watching the party as they make their way through the dungeon.
Akihabara was originally going to be explorable before being cut entirely.