Read the full review here.
“Overall, Mappy-Land is a very average game, if that “very average” phrase makes any sense. It will have its loyal adherents that have fallen into deep fondness with its mechanics and have mastered them, and it will also have its detractors who only grow further frustrated and annoyed with its play that can be downright difficult and annoying if you are not used to it.”
– from the full review, which you can read here.
Mappy-Land was produced by developer Taxan. They produced other NES titles, the first of which I can think of is 8 Eyes. The only reason I remember that is because, if you beat 8 Eyes once, you begin a second quest, and the password for that second quest is TAXAN TAXAN.
That had very little to do with Mappy-Land, just as the rest of my NES experience has.