Hardest game on a nintendo console?

Super Mario RPG (Snes) was really the hardest, especially the last level

super mario rpg was my first rpg, after that I played final fantasy 7 on the ps1, really a masterpiece both games by squaresoft before it became square enix.

from what I've heard, ghost and goblins for the NES

try battletoads on the nes, thats another level of insanity.

Super Ghouls and Ghosts

Super ghouls and Ghosts on SNES is definitely the hardest game I've beaten!

I'd argue Super Ghouls on SNES is the easiest one of the trilogy.  The first two were way harder!  lol