Custom Mega Man Boss

[Thanatos-Zero]

Of course this is pure opinion and preference. I honestly do not fully know how NES sprites function yet. This might violate some pixel limit or somthing (I really do not know).

Nope, this doesn't violate the limits. As long they fit nicely in the 8x8 tiles in your sprites, there is nothing to worry
http://en.wikibooks.org/wiki/NES_Programming

Don't use the 8x16 sprites though (even if you could put 8 vertically on a line), as they do not allow layers on themselves, also they eat up unnecessary space in the ROM because of their strange nature of being stored in there.
They are meant for games like Punch Out, which really use tall sprites.