Hobo 13

Planet Name: Hobo 13

Title: the finest military training planet ever

Appearances: Hobo 13

Inhabitants: Hobos, Hogulus, Plant monsters...

The harsh and dry planet of Hobo 13 serves as a training planet for soldiers. Other-worldly trainees hoping to become skilled soldiers come here to participate in a series of trials. Zim was sent here by the Tallest to prove he could pass in order to get a shipment of military equipment. The trials to become a soldier are to get across a molten pit of hideous creaming pain, navigate across a canyon that is home to the meat-thirsty Hogulus, get through a laser trench, cross a pool of acid, find the way out of a maze where a robotic snake-thing lurks, and get past a swamp full of plant monsters until finally reaching the Fortress of Pain.

The Hobo species identify themselves through numbers instead of names. For example, one of the drill instructors on Hobo 13 is Sergeant Hobo 678.