Big O is transported around Paradigm City and out into the country via underground railway tunnels aboard the massive, quad-engine carrier train called the Prairie Dog, which has a telescoping chute that can deploy and recover Big O on the surface. It apparently operates via remote, as Roger's butler Norman deploys it to different parts of the city from the mansion when his master has need of it. When not in use, it rests in an underground railway junction beneath Roger's mansion. In the manga, it is revealed that this transport also carries interchangeable arms for Big O that can be exchanged easily, something that is not shown in the anime.