Nintendo Hard is no joke. With todays games you get tutorial levels, save states, unlimited opportunities. NES was just like “you get 4 chances, don’t **** it up. Go.”
Rygar and Blaster Master were two games that I loved, but had no save points and took forever. You either had to plan the day to play it in one sitting, which could take hours, or hit pause, and hope no one turned off the NES or it didn't freeze/flick and pick it up later.
Those are two games on the NES channel that were my favorites as a kid, but I hated playing because you'd invest a crap load of time, but if you died or had to leave, you couldn't save.