This is how you beat bowletta. Firstly you have to be at least level 38. If you are still in bowsers castle try to defeat him. if he kills you you start at the bean bean castle. Go to the item shop and buy 10 ultra mushrooms 10 ultra syrups 10 ultra nuts and 10 1-up mushrooms. Equipt mario and luigi with these items: tank badge, casual slacks and an extra thing you got from the cafe thing. Go to bowsers castle.Now heres how you fight him. destroy his body parts. Leave his head for last or he will do something nasty to you. once you destroy every single thing on his body his heart will appear and it will restore all his body parts . keep attacking his heart with bros. attack. His heart will shrink back into his chest after a few turns. Keep doing that and he will soon be destroyed.