Hello my friends! I have a question about how to build a Character similar to the ESO Nameless Knight!

So, context for those of you that haven't seen it, please look up 'ESO knight' on Youtube and you should see this absolute unit 1v3'ing the main characters.

More context: I am playing in AV and am a Level 3 fighter joining the group. I'm an Angelkin Nephilim Human. We also can make use of the Free Archtype ruling. I have 250gp to spend and can purchase uncommon items.

I know he -is- a fighter but I was wondering what could help me get closer to his style of fighting thematically and things like that. Also, what type of, I guess you could say, build path he has as he would level up and the like.

I've been wracking my brain trying to best figure out how to do this so I figured I'd turn to minds greater than my own. Thank you in advance for all your help, my friends!