Due to a bizarre code interdepency in Super Mario Sunshine, Mario can gain permanent aggression to durians. While normally, he can handle them gently, if Mario enters a sewer and jumps once, he will become incapable of kicking them with anything except full force.
I love this photo of sweet Butter among the sunflowers - it truly shows how sweet and smol she was, just a tiny rat but she had the spunkiest personality and was always game to do anything!