This article presents the Origaker, a novel multi-mimicry quadruped robot. Based on a single-loop spatial metamorphic mechanism, the Origaker is able to transform between different working modes, as the reptile-, arthropod-, and mammal-like modes, without disassembly and reassembly. The combination of the metamorphic mechanism and the quadruped robot enables the Origaker to pitch vertically, twist horizontally, and change the positional correlation between the trunk and legs. In consideration of its reconfigurability and structure adaptability, gaits and movement strategies, namely, the fast spinning gait, the stair climbing gait, the self-recovery, packaging, and crawling through narrow spaces and right-angled bends, were proposed and analyzed, demonstrating that the metamorphic mechanism provides the robot with enhanced locomotivity. Finally, a prototype was developed and experimentally tested. The experiment demonstrates that the robot can crawl over various surfaces, execute the designed gaits and strategies on different terrains, and conquer challenging obstacles.