This is one of the best 8-bit covers I have ever seen.
The sound channels sound just like on a real NES. (most 8-bit covers like this use the wrong waveform for the bass channel.)
Only one thing is wrong: There is a (barely noticable) arpeggio at the very beginning. These sound effects were not used by Nintendo composers at the time. But meh, as if that makes any sense.
That was pretty badass.
This is even better than the original! And that one was already awesome.