This paper introduces a minimalistic design of a monopedal robot (monobot) with C-shaped legs which can achieve multiple locomotion modes (multi-mode) such as walking, leaping, as well as backward and forward flipping. The monobot contains an actuator, speed controller, 3D printed base frame and legs and battery set. The weight of the whole robot is less than 80 grams. Dimensional parameters are optimized to simplify the design process and to identify effective factors for locomotion. Potential locomotion modes of the robot are analysed by dynamics simulation. A simplified virtual prototype is tested within multibody simulation software. An experimental platform of monobot is also developed. The speed of the platform is adjusted to verify the correspondence between actuator speed and locomotion mode as obtained by simulation. Potential applications of the multi-mode monobot include disaster rescue, planet exploration and reconnaissance.