The Moon Monster is the main antagonist of "The Power", the first episode of the hit animated series Regular Show.
He was voiced by Mark Hamill of Star Wars fame.
Rigby sends several items to the moon, including "a bunch of baby ducks" (which resemble the ones from the episode "A Bunch of Baby Ducks") and "a soda machine that doesn't work" using The Power. He also sends the Moon Monster there.
The monster proceeds to attack Skips until Rigby uses "hamboning" to avert the crisis and save him. After Rigby escapes, the monster runs after the gang but was not able to kill them due to Skips fixing the power just in time for them to be able to teleport back to Earth.
The Moon Monster is very large, has Rigby's body, Mordecai's tail, and Beef Burrito's head. He also wears a belt with a golden belt buckle, somewhat resembling the one on the Beef Burrito doll. His fate is currently unknown, but he could still be living on their fictional moon and might be seen again if they travel to the moon again.
- He is the first Regular Show antagonist.
- In his original concept art, he was going to have a beard.