Fight Fire with Fire by Metallica
Generally, this song isn't too bad...until the very end. Those "Fight fire with fire" phrases need to be hit perfectly, otherwise your combo will be jacked. I grinded it for almost two hours the other day, and missed the last pitched phrase twice. This came the very next run after the second one. I was shaking so bad that night after I got this. Also, ignore what I say at the end, I tend to get really orgasmic after stuff like this. But it's such an awesome song, probably my second favorite song on the Ride the Lightning album, behind Fade to Black, and that's why I didn't mind grinding it.
And just for the record, I did this on the 360 version of this game. I got it for the Wii the other day, but haven't done that much with it. Also, please excuse the dark background; I don't have a capture card or such, so i'm forced to record on my iPhone, and the lights were out when I was recording.