DMC4: Special Edition - Nero vs. Berial Bossfight GMD (Gods Must Die) SSS, No Damage

First: I'm very well aware that Nero is way easier than Dante or Vergil as I have tried it with these two as well and... simply said, I still have not defeated him with these two, tho I am close with Vergil. Second: I'm playing with Keyboard.... yeah, I know I'm insane Altho it was a No Damage Fight, it didn't went nearly as flawless as planned. At 1:08 you see a huge Screw-Up by me, I tried to go for a Calibur but completely failed at doing so, this was meant to be followed up by a Buster on Berial's head. As you can see this threw me off so much that I failed the Buster again when I got on his head... in the end I SOMEHOW got away witout taking a hit.... huh