This chapter introduces a novel four-limbed robot, WAREC-1, that has advanced locomotion and manipulation capability with versatile locomotion styles. At disaster sites, there are various types of environments through which a robot must traverse, such as rough terrain filled with rubbles, narrow places, stairs, and vertical ladders. WAREC-1 moves in hazardous environments by transitioning among various locomotion styles, such as bipedal/quadrupedal walking, crawling, and ladder climbing. WAREC-1 has identically structured limbs with 28 degrees of freedom (DoF) in total with 7-DoFs in each limb. The robot is 1,690 mm tall when standing on two limbs, and weighs 155 kg. We developed three types of actuator units with hollow structures to pass the wiring inside the joints of WAREC-1, which enables the robot to move on rubble piles by creeping on its stomach. Main contributions of our research are following five topics: (1) Development of a four-limbed robot, WAREC-1. (2) Simultaneous localization and mapping (SLAM) using laser range sensor array. (3) Teleoperation system using past image records to generate a third-person view. (4) High-power and low-energy hand. (5) Lightweight master system for telemanipulation and an assist control system for improving the maneuverability of master-slave systems.