It took me about 3 months to get thru the last boss of the last arena...including a few episodes of rage quitting for a week. I remember reading about how when others who had struggled finally beat it, they we're ecstatically elated. When I finally beat it, I just stared at the screen and said to myself "God that sucked."
Since then I've probably beat it 50-60 times, got all the gear (99% of which is utterly useless). About the only time I felt good about it was when I got the bows and fire staffs. Other then that, I don't think I've ever ran such a miserable piece of gaming content in my life.
PS: Wait until you get to experience the utter RGN bull crap of the poison flowers (Arena 7).