 Dr. Mario is a falling block tile @-@ matching video game , in which Mario assumes the role of a doctor , dropping two @-@ colored medical capsules into a medicine bottle representing the playing field . This area is populated by viruses of three colors : red , yellow , and blue . In a manner and style considered similar to Tetris , the player manipulates each capsule as it falls , moving it left or right and rotating it such that it is positioned alongside the viruses and any existing capsules . When four or more capsule halves or viruses of matching color are aligned in vertical or horizontal configurations , they are removed from play . The main objective is to complete levels , which is accomplished by eliminating all viruses from the playing field . A game over occurs if capsules fill up the playing field in a way that obstructs the bottle 's narrow neck . 
