B-Daman

B-Daman is a Merchandise-Driven manga and anime franchise produced by Takara Tomy, based around small, customizable robot figures that shoot marbles from their torsos. The name is derived from the Japanese word for marble, bidama. Marbles used in the game are refered to as "B-Dama", a marketable transliteration of the word, and can be made of many different materials; while the series is mainly known for using clear glass marbles, metal, plastic, rubber, and hybrid marbles are also common. The performance of each B-Daman is determined by the type of core it uses, in addition to other accessories that could improve the ammunition capacity, mobility, accuracy, power, or shooting speed. (Source: TVTropes)