I already went to the lilycove team aqua hideout after beating the elite four, but the master balls weren't there! So frustrated; I need a master ball really bad. :( CAN SOMEONE PLEASE HELP
No, you can't. It's a one time thing once you first get there. But you can get another one after you beat all the contests in lilycove city. You can also win first prize on the lottery in lilycove department to get another.