Continuity mistake: When Batman goes to save Martha, he pulls the wooden box with his gun and throws it at one bad guy. The guy's head hits the wall, leaving blood. Later on, you still can see the dead guy but there is no blood on the wall any more. The blood appears again when Batman is about to finish off the last person who was stabbed and pinned against the wall. (02:17:30 - 02:18:35)
Continuity mistake: In the beginning, Bruce Wayne drives his car towards all the chaos, but the crowd is too thick for him and his car to get through, but with movie magic suddenly Bruce and his car are at the front of the crowd. (00:07:00)
Chosen answer: It is Flash. He is wearing armour because of whatever has transpired in the future. He often wears an armoured suit in dire circumstances in the comics.
Also, if you look at the bottom of the image frame you can just make out the Flash icon on his chest piece.