Holy shit....well I gotta say that when it comes to the whole Mario overshadowing Luigi joke has gotten overused, I will say the sprite animation is absolutely top-notch. Like I'll say this, your art style does need improving in the anatomy department. Especially your hands as the hands on the character look a bit oversized. The character's bedroom was too light as well which made me not notice it until I looked closer. The proportions and such of the room could look better as well.
But as I said, regarding your sprite animation and even spriting, holy crap you did a great job. The way you did the character rotation with NES SPRITES no less was nothing short of astounding. The movements were fast-paced and even the effects used were awesome, too. I just love it.
As I said, proportions and anatomy could use work but if you do make more sprite animation, I'd like to see what you could cook up, man. Good job.