I think a lot of people will say Bomberman and with much reason to. Bomberman was originally known as a cool great 4 player game where you blew up your friends with bombs, then it totally went left field crazy and tried to be so many things it wasn't. It started with crappy RPG Bomberman attempts that I kinda enjoyed at the time cause the power ups to Bomberman's bombs were just permanent. Then it just all went downhill when they decided to make crappy party games and dumb futuristic Bomberman!.

Runner ups are of course: Castlevania, and Sonic. I think these Franchises are really just hurt by the fact that there really is no way to evovle them. Keeping them 2d is always great but when you do they do that they never innovate and people who like 2d games are few and far between now a days!