Metroid, always critically acclaimed save for a few stinkers here and there, always recognized for a lot of good things and never sells above 3 million, kirby somewhat it doesn't seel bad but it always rounds to Metroid like numbers, except it has a LOT more games than metroid, someone would expect that a franchise with such a mascot would have seen some better sellers here and there,mmm, let's see i would say no more heroes it's true that they are M-rated games that came first to a "family friendly" console, that they aren't the best of the best and they weren't some big budget overblown productions, but they took forever to sold like a few hundred thousands even when re-releasing in other platforms, but maybe thery are just too niche,
I also agree with the choices of Salnax, Ace Attorney is freaking brilliant and despite having a good amount of games re-releasing several times it hasn't reached 10 million, the Prof. Layton series basically doubles Ace Attorney despite having less games and most of them on DS and 3DS, Bayonetta, same for this, someone would expect that a game about a hypersexualized heroine would be just a tiny bit more succesfull if due to all the noise some people make about her, Shin Megami Tensei games that aren't Persona should get more recognizion, they have been there since PS1 and PS2 days giving more variety to the catalog.
I would add Wario games both Land/world(and nintendo really should launch a new one) and Ware series, it's true that they are more experimental that other franchises, but that's their charm and i love them for that and all the humor, if mainstream consumers weren't just onto the same franchises time and time again, they would see that there are a lot of tinier games that are as if not more entertaining that some of the big budget games, or in the case of wario ware series that some cheap mobile knockoffs.







