https://www.cnet.com/news/all-avengers-endgame-trailers-and-posters-in-one-place/

Their secret weapon to make sure this new plan works is none other than Captain Marvel (Brie Larson) herself. Captain Marvel reminds the group she's been away saving other planets that don't have their own version of the Avengers to protect them. 

The clip also comes with a new tagline, "We owe it to everyone not in this room to try."