King Carp saw a greninja talking to the rest of the group before walking off. Curious, he decided to follow him. Maybe he could find the Mightyena, or that Torterra. Even if he couldn't, King Carp felt that if the Greninja was attacked by the Mightyena, he wouldn't be able to beat them all alone, and King Carp owed the group a debt for rescuing him.