Aerial Assault Trooper is the new outfit skin in Fortnite Battle Royale.
It is a rare set.
How to get
You can buy the Aerial Assault Trooper at the Season Shop.
It requires you to reach Season Level 15.
Unfortunately, it is not available now.
As mentioned, Aerial Assault Trooper will be only unlocked when you step into the Stage 5 in the current season.
Additionally, you are asked to purchase it.