I just noticed that rather than simply being a Mega Cartridge, Shinobi on SMS is a Two-Mega Cartridge and its "Mega Type" is listed as Two-Mega. Since it is but a single cartridge with a single game upon it, I'm not sure what the two-mega is referring to. My guess is it's a measurement of the size of the game, but what is a "mega"? Definitely not a megabyte or megabit because those would be far too large. But, enough guessing, does anyone know what this is referring to?