It helps that mappers added a lot of functionality. IIRC Super Mario Bros. is the "best" you could do on base Famicom hardware. Later titles typically rely on m

It helps that mappers added a lot of functionality. IIRC Super Mario Bros. is the "best" you could do on base Famicom hardware. Later titles typically rely on mappers to allow for not only increased game size but potentially improved sound, and graphical effects like scrolling in multiple directions, saving, etc.