Leitner is one of the many planets in the universe.
Leitner was one of the many planets observed by the Chronicoms, with Isaiah being the main anthropologist sent to observe and record the evolution of the intelligent species populating it. However, while other civilizations on other planets had gained significant knowledge in various technological fields, the population of Leitner progressed very slowly. As such, in 2019, the inhabitants of Leitner were still unable to build real houses, instead living in caves, and used feces as combustible for cooking.
Due to this lack of technological advancement, many of Leitner's landscapes and environments were free of any source of pollution, which was why Boyle and Toad planned on emigrating on Leitner to live a wealthy life there.
- The name of the planet is a reference to the Agents of S.H.I.E.L.D. writer and producer Mark Leitner.