https://www.cnet.com/news/all-avengers-endgame-trailers-and-posters-so-far-here/

More glimpses of new footage of Captain America, and Iron Man and the rest of the Avengers getting angry during battle somewhere that looks like a destroyed city's ruins. Plus Rocket Raccoon says, "Alright Avengers, time to live up to your name." 

This teaser trailer shows a lot of the same footage we've seen in previous trailers, but there's a quick clip of Natasha Romanoff/Black Widow saying the Avengers are her family. There's also a clip of Tony Stark (Robert Downey Jr.) telling Steve Rogers/Captain America (Chris Evans) he missed Cap's "giddy optimism."