So with Color Splash's release there has been a lot of talk lately about how it lines up with the other Mario Adventure/RPG games that preceded it. In the beginning, we had Squaresoft kicking things off by giving us the world's first-ever Mario RPG on the SNES, and then fans would see the series sort of split into two paths: Mario & Luigi on handhelds and Paper Mario on consoles. The latter series have both seen numerous sequels, and there is no general consensus on which entries in their respective series were the best. While both Paper Mario and Mario & Luigi have certain recurring thematic and mechanical elements that crop up in every game, they all also excel and in some cases come up short in specific areas each time around. One staple of nearly every Mario RPG game is a solid translation effort, and that extra bit of charm helps flesh out the personalities of characters old and new even further.
But I don't want this thread to devolve into an argument about which Mario Adventure/RPG is best. No, I'd rather focus on which one did the best job expanding on the universe of Mario. Since mainline Mario games tend me to very minimal and safe in their world-building and storytelling, many Nintendo fans look to spin-off games to flesh out the Mushroom Kingdom and its surrounding areas. These adventure games usually give players the opportunity to actually speak with characters that are usually nothing more than obstacles for Mario. It fleshes out the personalities of the Mario cast and crew while also giving birth to new characters that sometimes become staples of the Mario-verse moving forward.
Since I'd be remiss to start the discussion without giving my two cents, I'm gonna give my vote to Mario & Luigi: Superstar Saga on the GBA.
This was a tough one since the original Paper Mario on N64 does a terrific job expanding upon the Mushroom Kingdom, but of all the vacation destinations that Mario has visited on his spin-off outings I think that the Beanbean Kingdom was the most interesting neighboring area. The first Mario & Luigi game had the perfect balance of new and interesting locales/characters mixed in with familiar Mushroom Kingdom places and faces. The beginning act in Mushroom Kingdom was a lovely depiction of the familiar setting, complete with shops and various denizens going about their daily lives. Beanbean Kingdom, on the other hand, is an equally interesting zone with its clever parallels to its neighboring Mushroom Kingdom while still having its own unique identity.
I've gotta say, though. If it weren't for the over-reliance on generic Toads and Shy Guys in Color Splash, Prism Island would be a definite contender. While the game drops the ball in terms of NPC variety, it really excels in terms of its setting. Prism Island is memorable, visually interesting, and diverse in its locales. Great stuff.
But I don't want this thread to devolve into an argument about which Mario Adventure/RPG is best. No, I'd rather focus on which one did the best job expanding on the universe of Mario. Since mainline Mario games tend me to very minimal and safe in their world-building and storytelling, many Nintendo fans look to spin-off games to flesh out the Mushroom Kingdom and its surrounding areas. These adventure games usually give players the opportunity to actually speak with characters that are usually nothing more than obstacles for Mario. It fleshes out the personalities of the Mario cast and crew while also giving birth to new characters that sometimes become staples of the Mario-verse moving forward.
Since I'd be remiss to start the discussion without giving my two cents, I'm gonna give my vote to Mario & Luigi: Superstar Saga on the GBA.

This was a tough one since the original Paper Mario on N64 does a terrific job expanding upon the Mushroom Kingdom, but of all the vacation destinations that Mario has visited on his spin-off outings I think that the Beanbean Kingdom was the most interesting neighboring area. The first Mario & Luigi game had the perfect balance of new and interesting locales/characters mixed in with familiar Mushroom Kingdom places and faces. The beginning act in Mushroom Kingdom was a lovely depiction of the familiar setting, complete with shops and various denizens going about their daily lives. Beanbean Kingdom, on the other hand, is an equally interesting zone with its clever parallels to its neighboring Mushroom Kingdom while still having its own unique identity.
I've gotta say, though. If it weren't for the over-reliance on generic Toads and Shy Guys in Color Splash, Prism Island would be a definite contender. While the game drops the ball in terms of NPC variety, it really excels in terms of its setting. Prism Island is memorable, visually interesting, and diverse in its locales. Great stuff.