"The Key to the Universe" is the twenty-first episode in Season 8 (and two hundred and thirty-eighth overall) of Regular Show. It aired on November 10, 2016.
The guys learn about Pops' true origins and Pops begins his training with Earl to become the Chosen One and fight Anti-Pops.
- Muscle Man
- Hi Five Ghost
- Anti-Pops (vision)
- Huge Head (cameo, skeleton)
- This episode continues from "The Ice Tape".
- This episode marks the first appearance of 2016 Cartoon Network Productions logo that serves as a successor to the 1999 one.
- The Death Star from the Star Wars franchise makes a cameo as Pops' fist crashes through planets in the flashback.
- When Pops is fleeing through the park passes by the skull of Huge Head, in the scene of the episode men in uniform, of season 6.