Death-Ball creatures emerge within the training courses of the Kero Ball device. They act as obstacles within pinball machine-like courses, actively pursuing participants during challenges. In the initial course, multiple Death-Ball creatures chase individuals. Later courses feature larger groups, with hundreds swarming and attacking participants simultaneously. Their design incorporates auditory and symbolic elements referencing another character, including a distinct vocal pattern and an affinity for sweets. The character's name itself utilizes phonetic similarities through its pronunciation.