I barely managed to solo the entire vault of glass, only using a sword, and then poof... Some dude with rocket launcher arms pops out named Xylar! He just fired non-stop, and to my dismay, he warps! After 18 hours of fighting him, I had him down to 99% health. I gave up. Maybe there's a way to beat him? [spoiler]Xylar the timeless[/spoiler]