Tony Tony Chopper (トニートニー・チョッパー, Tonī Tonī Choppā) is the doctor of the Straw Hat Pirates. He is a blue-nosed reindeer, who gained human properties by eating the zoan-type devil fruit called Human-Human Fruit (ヒトヒトの実, Hito Hito no Mi). The fruit-granted ability allows him to change between three forms. His first and original form is that of a reindeer. In his second form, he has the proportions of a human child, while retaining his antlers, hooves, and fur. In his third form, he looks like a brawny man with fur. In addition to his normal transformations, Chopper developed a drug he calls Rumble Ball (ランブル・ボール, Ranburu Booru), which allows him to assume four additional forms for the duration of three minutes. These forms focus on certain aspects of his body to improve his physical abilities. These are broken down into "points" in the Japanese version and "boost" in the English versions called: guard, horn, jumping, and arm point with the original three becoming walk, brain, and heavy point. If Chopper uses a second Rumble Ball within six hours, he cannot control his transformations. If he uses a third Rumble Ball within six hours of the first, he transforms into a monstrous version of himself and loses all self-control. He also has the ability to understand other animals' speech, because he is an animal himself. What he is not capable of, however, is hiding his feelings.