For the easiest way to beat the shadow, grab regen for sure. The skill relating to stun time (It's a kong forbidden word?) might be necessary too, but don't know. Climb on top of the right overhang and face to the left. Now just stand there, and collect gems every once in a while. Its attacks won't kill you (And as long as you stand still, you'll regen quick enough to be back at full health), and its attacks push you toward the wall. Then, it keeps attacking while you're stunned. And boulders hit it. So, you stay alive and hurt him at the same time.