A few years ago I created the Classic Style Colossus from a 10" Stark Raven figure.  This time around I re-created him using the base figure but in his "Ultimate"  outfit.  Tons of Dremeling had to been done again to remove all of the original figure's detail. I then needed to sculpted on his hair, ears  and belts with my Magic Sculpt Putty.  For his black stripping I went with really thin black tape. You can buy it at most hobby stores that carry radio controlled cars. It's called "Pro Line Racing Tape" or "Pin Stripping". It made it much easier then trying to paint the lines on the figure (and much cleaner!). On my last version, I hand painted his metal skin.  But not this time.  Ultimate Colossus got the airbrush treatment!  This allowed me to make his metallic skin much more realistic!