Unique from the other two Mario games for the NES, but still a great one.
The cool thing about this game is, though, that you can be one of four characters: Mario who runs fast but doesn't jump high, Luigi who is the opposite of Mario and he can jump long distances, Toad who can hardly jump at all but his speed definatally makes up for that, and Peach who as far as jumping and running is about equal but she can hover in the air if you hold the button down, and it lasts for about 3 seconds.
One downside about this game is that it is only one player. You would hope with those 4 characters available, you could play 2 player. Sadly, no. Though that doesn't mean you couldn't try taking turns, it could still be fun.
All in all, this game is pretty decent and fun, the graphics are colorful and that's what I, personally, like in a game. Though instead of jumping on top of an enemy to squish it, you jump on top of them, pick them up and throw them at another enemy or you can throw other obsticles at them. Give it a try!