One of the best games on the NES, top 3 game on the console.

Gameplay doesn't get any better. You get to flip up and down between gravity on the floor or the ceiling, which makes traversing thru levels very unique.

Soundtrack is good but not great. The animations are also pretty good for an NES/Famicom game.
Boss fights are all fun,, with 1 particularly hard motherfucker near the end.

A must-play for the console.