arrow keys to move. z,x,c to attack. C is the ultimate smash, though, so you can't use that until you have the power. You have to wait for the power to come within you. If you see more than one shadow, that's totally normal. One of them will disappear. This is a start, right?
some notes: This was a bit easier to do. I did a few things differently, but this limited some of my capabilities, so some of Shadow's moves are different. Apologize it is pretty glitchy, but at least this works, right? ;3 The variables are there just so you can see what's going on.