download ROM here: https://tcrf.net/File:Super_Mario_Bros._2_(USA)_(Prototype).nes (disclaimer: only download ROM if you have the actual game (original game counts)) Super mario bros 2 was a vast game, filled with secrets and treasures. However, a beta version has been found and it can be noticed that there are differences. For example, press A on the starting menu, and your start world will change. (note: do not press 8 times, it breaks your rom) Press SELECT for 15 extra hitpoints. And, you start with 19 extra lives. Press A 10 times to get the third image shown. Well, I'm off to play my prototype.
played on google Chromebook with a GPEMU emulator. NESticle also works for windows users.
