I love Super Mario Bros. 2. It may have been a game in Japan called Doki Doki Panic, but it’ll always be Super Mario Bros. 2 to me.
The japanese version of Mario Bros. 2 is tough as balls. Damn bloopers are everywhere!
The Lost Levels? The U.S. got that in the early 90s with the Super Mario All-Stars SNES remastering. It’s damn near impossible on the NES. I was able to play the NES version thanks to the Wii’s arcade market that let’s you play original games. The SNES version let’s you continue at each level, which makes it more doable.