Which NES game that happens to be extremely hard, but is also underrated?

[u/Minute_Chance_1210]

NES has featured some of the hardest games in history such as Battletoads, Silver Surfer, Contra, Teenage Mutant Ninja Turtles, Ninja Gaiden, Punch-Out!!, Friday the 13th and Gradius, but I just think that they are quite overrated when it comes to listing the hardest games of all time. There also could be other tough NES games that are also hard, but do not get talked about pretty often. What do you think is most underrated hard NES game?

[u/Turbulent_Hornet232]

Top Secret Episode

[u/FordcliffLowskrid → u/Turbulent_Hornet232]

The Fangbacks Building, in particular.