I know! It took me a while to figure it out, but here's how:
First, just press A rapidly while he's trying to suck you up Then, when he starts to suck in the bomb berries, grab them with B and don't let go of them until he starts trying to suck you up again. Then press B again to drop them in his mouth! You have to do this 3 times to beat him. Hope I helped! :furawatchi:
