[Swordstriker21]

Well about the "Shining Giga Drill Breaker" Kirito pulled off in the end...

Spoiler for Novel Comparison:

It was just A1 pulling off some "artistic" flair. In the novels it was just him slicing through the horde at very high speeds w/ the dual swords. Just enough that the spawn rate didn't have time to keep up w/ the kill rate. And he did it fairly close to the top and only managed to get through a very small opening. Like threading a needle. It was all they managed to do even w/ the entire Sylph/Caith Sith army backing them up.