GoodPuffer has the appearance of an anthropomorphic pufferfish and is entirely yellow, with his torso being slightly brighter. He has spikes on his torso and possibly on his back, although they are not visible due to his design. He resembles an Arothron meleagris (yellow form) or a Takifugu pufferfish, which is his suggested species. His design has remained consistent and unchanging. Although mostly hidden, GoodPuffer does have fangs.