Aiight time for me to have a crack at it

Vision: At first glance it's already an eye candy, visually it looks really appealing with using a good amount of the red which feels dark and aggressive. The eyes are sold to me cause they're just awesome!

Originality: Though Shadow is mainstream, at least it wasn't like a sonic redesign since I've seen so many of those so. I'm a big fan of mecha stuff and mecha parts and I really like the design you made for him around the big bulky shoulders and forearms. It would be cool if you made it more neon lights on the emerald icon, personally I would use blue cause blue and red is my favorite contrast but I know why you got the color.

Technique: I feel the character could use some more shine, mostly on the head cause it't the main focal point. Other than that you're coloring is spot on. There's one area I feel a little about and it's his muzzle. It just feels flat to me. Maybe if you brought up his cheeks a bit more cause I know you're going for the dont fuck with me face but it shouldnt kill the feel if you brought up the sides of the muzzle up just to give it some cheeks.

Impact: Overall this is one of my favorites, love the design, I always love your style. Hopefully I made a good critique. I can see better on other work than myself xD

Keep it up bro!