As a hunter you have no chance. The atheon battle alone requires either a 4 guardian team or a whorelock with self revive. You'd also struggle at the templar but all the way up to the big boss himself you're pretty much good to go. It took 6 of us all above 290 light to drop atheon on his ass in roughly 20 seconds so it's possible to do, did you not see the video of a whorelock soloing it before HoW came out? Check it out if you're gonna give it a go, the guy had it down :-)