Now I know, I need to jump the platform, at the same time spin that wheels in order to cross the valley. After which, it's consider pretty easy, some jumps and finally meeting the big boss. I thought I'm smart enough and able to get over it, but somehow nothing happens. No matter how hard I try, I just couldn't chase after the boss. Not sure how many times I've attempt, and I had to give up due to the video length. I'm gonna go and study some other people's walkthrough to see how they defeat the boss.
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