The Battle Royal Single Player mode takes place in the Battle Royal Dome in Royal Avenue. Here, you will be able to participate in Battle Royals with NPc characters. Like the Battle Tree and past Battle facilities, the trainers within the Battle Royal will use random Pokémon from a set pool of possibilities.

There are four different ranks to battle through in the Battle Royal
Normal Rank
Super Rank
Hyper Rank
Master Rank
The rules to this are the same as the Battle Tree where you can't use Special Pokémon, Same Pokémon or two Pokémon with the same items. When you participate, you will get given BP regardless of if you win or lose, but a higher amount if you win. If you defeat the Master Rank, the Pokémon you use will be given the Battle Royal Master Ribbon. All Pokémon you face will have a random one of their abilities.