Previously I said that I think Super Mario Bros. 3 is the best NES game, but I think Kirby's Adventure comes extremely close. Really late release in the NES' life, but also one of the best designed and best looking. Love the music, the graphics, the Copy Abilities, the little story, everything. I think the only thing that's a little annoying these days is that you drop your Copy Ability every single time you take damage.