Monorail is a monorail Zenblock and Memnock used to visit when they were kids. In Zooper Noobs!, they recalled their childhood memory.
The monorail is managed by Mr. Monorail, the head of the monorail or the captain on board. Zenblock and Memnock love him. During Zooper Noobs, Mem and Zen decided to ride the monorail to relive their childhood memories but they get imprisoned there by the zoo keeper to prevent them from rescuing the noobs from zoo captivity. However, Mem and Zen did not know they were being imprisoned as they were having too much fun to notice. They get rescued by the Noobs after they break out of captivity.
- Zenblock and Memnock used to visit the monorail when they were kids. This implies them be be brothers or childhood friends as they most likely went to the space zoo with their parents to ride the monorail