The teaser trailer is probably the opening cinematic of the upcoming video or just a new short video that shows more cinematics and probably a bit of a background of what the game is all about. The description does tell that this will show the events that will trigger the all-out war that is happening in the main game.
“The world wants to forget we exist,” starts the teaser. “We will force them to see.” It them some very short clips of a storm in the sea, planes flying towards it, streets flooded with one soldier running towards something, and then it cuts to the premiere date.
Battlefield 2042 Exodus short film will premiere Thursday, August 12, 2021. It then lets the viewers set a reminder on their accounts. The main game launches October 22, 2021 on PlayStation 4, PS5, Xbox One, Xbox Series X/S, and PC.