Marvel Studios: Avengers Age of Ultron New Trailer!

So we have another trailer for Avengers Age of Ultron. Still no Vision, and not much more of Scarlet Witch or Quicksilver. But that could be a good thing, something to look forward to when the film is actually released. There are a few things to take note of during this trailer though, more Hulkbuster armour, more hints that Stark created Ultron, but most importantly, for me, what looks to be a female character in a cave, is this to do with the arrival of Black Panther? Certainly looks Wakandan like don't you think? If not who is this mysterious character who has appeared and what is their link to the film and wider Marvel Cinematic Universe? Well anyway now I can't get that creepy tune out my head... "there are no strings on meeee"... check out the new trailer below;