Tweeted by the guy from IGN
The full trailer also had a glimpse of the mask of a major DC villain seen at once point (no one was wearing it - it looked to be stuck on a spike or such on a beach). If you want to know who it is, check out my tweet about it. Oh, and the full trailer made it clear he just calls himself Arrow, not Green Arrow.
Holy crap, this might be spoilery for Arrow, but there is a glimpse in trailer of what I am 90% sure was... Deathstroke's mask!
Wow I can't wait to see how this turns out. Meow.