Hybrid

I've been thinking about a new story that's been bouncing around my head for a while, and I've finally gotten an intro down on paper.  If you care to read it:

     Underwater.  He was floating underwater.  Strange lights played across his vision in hues of blue and green.  He raised his right hand to touch them, and it glinted silver.  His arm was metal, with blue crystal lining the seams.  The lights pulsed again, and feeling flooded into his hand.  Fire and lightning crackled around the metal hand and suddenly coalesced into a burning blade extending from his wrist.  Another hand floated into view, twisted with sinew and tendons tense underneath the taut skin.  He flexed it experimentally, and feeling shot through his left arm.  With a slight burning sensation, a long claw sprouted above his wrist and extended itself until it matched the fiery blade on his right.  Suddenly the water started dropped away, and he was standing.  He looked down at his body, a blend of smooth machinery and muscular flesh.  Clothes appeared on him, hiding the hybrid body from view.  The lights he had seen earlier also disappeared, and he saw that they were arc lamps, similar to ones used in surgery.  A short doctor was slumped in a chair behind them.  He walked over, and the old man looked up.

“Now you are complete, my brother.  They cannot hurt us any more.”

Then he fell back, and the room disappeared in a screaming wind.

The only problem is, that's about as far as I've gotten.  If you people could give me some advice here, or just a base idea, I'd be grateful.  I'll get back to you in about a week, as I'll be a few thousand miles from my computer for a while.  When I'm back, I'll look at the feedback (if any) and pick something out of there.