Chadwick Boseman was a guest on Jimmy Kimmel Live! Thursday night, and he brought along a new clip from Captain America: Civil War. We knew he fought Winter Soldier in the film as Black Panther, and now we get to see that in action.
The clip shows an extended sequence of Black Panther in full costume fighting Bucky, who is very much on defense. Based on Cap's dialogue when he jumps (literally) into the action, this must be the very first time they see Black Panther, as they don't know who he is at all.
Boseman said "the stunt double had to fight me to be in the suit," and he tried to stay in the midst of the action scenes as much as he possibly could, during his interview. The fighting style for Black Panther is certainly unique to any other characters in the Marvel Cinematic Universe, with some cat-like movement and a lot of Capoiera-style quick slashes and kicks with a low center of gravity.