Lord Betrayus is the supreme ruler of the Netherworld and of all Ghosts and Monsters and acts as the main antagonist of Pac-Man and the Ghostly Adventures. His primary goal is to steal the power berries and take over Pac-World and rule it with an iron fist.
Growing up, Betrayus always lived in the shadow of his brother Stratos who was more liked, more popular and the preferred son of their mother Rotunda. As a child, he received very little respect from others, and even his mother seemed to care very little about his needs. He also had a deep hatred towards Halloween, due to his mother forcing him to wear the same exact mustard costume until he was an overgrown teenager. During his teenage years, Betrayus was a professional Pac-Pong player and one of the best until his match against fellow Pac-Pong expert Spheria Suprema, who managed to beat him with a score of 21 to 20 and she became the reigning Pac-Pong champion. The loss left Betrayus emotionally scarred for the rest of his life and afterlife due to the humiliation and the fact that he had an unreciprocated crush on Spheria at the time.
Before the events of Pac-Man and the Ghostly Adventures, Betrayus led a massive revolt against Pac-World in a plot to take over the world and somehow managed to recruit ghosts from the Netherworld to aid him and acquire powerful weapons and vehicles for his invasion. During this revolt, he laid waste to many locations with his army of soldiers and ghosts, striking fear into many and even putting the rebel Resistance on edge. However, despite the fact that he had ghosts serving him and the fact that he was well-armed, he was eventually defeated. As punishment for his crimes, he was stripped of his corporeal form and banished to the Netherworld. Since then, he has been waiting and plotting for the day when he can gain revenge on all Pac-People.
After many years of imprisonment, Betrayus and his army were finally freed by Pac-Man after he accidentally opened up a portal to the Netherworld, but is distraught when he realizes that Pac is the last yellow Pac-Worlder left in Pac-World and the only one capable of stopping his plans.
In the Legacy of Chris Thorndyke,
And he is reprised by Samuel Vincent in the English dub and Tsuguo Mogami in the Japanese dub.