A new free standard arena has been added to the Rocket League Casual and Competitive Playlists and Private and Exhibition matches. The new arena was released along with update 1.24, which also brings new vehicles, items, crates, painted wheels, new trophies/achievements, and more.
The new arena, which is called Aquadome, has players journey into the depths of the sea and compete at the bottom of the ocean. Two ocean-themed premium DLC cars will debut with AquaDome and are available to purchase for $1.99/£1.69/â‚¬1.99.
You can learn more about this update in the patch notes here.
Source: Rocket League