User blog comment:SPARTAN 119/Connor (Assassin's Creed III) vs Hei (Darker than Black)/@comment-422690-20130201021712

Hei wins this one by far. Not only is his coat bulletproof enough to withstand repeated shooting from multiple types of firearms, he's also used to facing and fighting superhumans. His in-universe nickname, The Black Reaper, was earned because he is one of the best at killing superpowered individuals, known as Contractors. He got that nickname during Heaven's War, during which he was not only a teenager, but he also had no powers at the time.

Connor will put up a good fight, but when you can fight at the level Hei can, you've really got very few competitors outside of OP superpowers.