https://www.gamespot.com/articles/fortnite-patch-notes-update-602-disco-domination-q/1100-6462410/

Epic Games has launched patch 6.02 for Fortnite on PC, Xbox One, PS4, Nintendo Switch, and mobile. The update introduces a funky new Limited-Time Mode centered around dancing and a powerful weapon for Battle Royale, while Save The World gets a special new weapon too. [Update: Epic has deployed a hotfix update for Disco Domination mode, increasing the score teams need to meet to win and decreasing the rate at which the storm circle closes in on the island.]

The new Limited-Time Mode for Battle Royale is Disco Domination, which was recently teased in-game. This mode is effectively King is the Hill; players are divided into two teams of 32 and will need to capture specific points--in this case, dance floors--by dancing on them and defending them from enemies. The more friendly players dancing on a floor, the faster it will be captured.