[2023] How to unlock arcade battles?

Originally posted by PsychoNekoBoi:

Originally posted by Black_Fox: There is a fold down menue under the "To Battle" button where he can select the game mode and server.

AFAIK he doesn't need to unlock any of the modes

No Arcade mode doesn't even show up, apparently he had to play 5 ground battle (AI) battles first

Brand new players needs to play few "initial" battles before they can select all the modes.