Despite being a protagonist character alongside Mordecai, he has done many villainous deeds that are unacceptable, but he has done things to fix his mistakes as well. As the series progressed, Rigby has gotten less and less antagonistic and has become more of a true friend and has even become a loving and devoted boyfriend and future husband to Eileen.
He was voiced by William Salyers.
- The Power: Steals a keyboard from a wizard and inadvertently sends Skips to the moon.
- Just Set Up the Chairs: Plugged in The Destroyer of Worlds game, so that he could play the game, even though Skips put a note forbidding anyone from playing it.
- Death Punchies: Wanted to get vengeance on everyone who beat him by punchies all the time.
- Grilled Cheese Deluxe: Steals a grilled cheese sandwich from Benson and lied to Mordecai about buying it.
- The Unicorns Have Got to Go: Brought in a gang of unicorns, which caused mass destruction in the House.
- Don: Rigby antagonizes his younger brother Don because he is bigger, richer, and friendlier. This leads to him sending Don away and nearly destroying the park.
- Ello Gov'nor: He smashed up a British taxi with a tree
- It's Time: He repeatedly makes Mordecai jealous when he announces his plan to go out on a date with Margaret.
- Appreciation Day: He and Mordecai edit the Book of Park Records to make themselves seem like better employees than they already are. This leads to the creation of Snowballs the Ice Monster and the near destruction of The Park.
- Do Me a Solid: He didn't want to hang out with Eileen, so he made Mordecai do him 10 solids, which were humiliating.
- Karaoke Video: He (along with Mordecai) excitedly manage to accidentally trash talk Benson, Pops, and Skips.
- Bet to be Blonde: Cheats during a bet so he would win.
- Skips Strikes: Bets the souls of himself, Mordecai, Benson, and Pops with Death if they lost a bowling match.
- Terror Tales of the Park (In the House): Threw eggs at an evil wizard's door, which was illegal.
- Fortune Cookie: Switches his fortune cookie with Benson's to get better luck, putting Benson through many terrible predicaments. In the end, it was shown that Muscle Man switched Rigby's cookie earlier.
- Diary: Broke Margaret's diary, though this was an accident
- Death Bear: He lied about a "local legend" and brought Mordecai, Margaret and Eileen to the abandoned Zoo where Death Bear lives. Which almost had killed Mordecai, Margaret and Eileen.
- Do or Diaper: He (along with Muscle Man) make a bet - if Mordecai can kiss Margaret by midnight Friday, Muscle Man will wear a diaper for a week. However, if Mordecai fails, he has to wear a diaper for a week.
- Wall Buddy: He divided the room with Wall Buddy, leaving all the trash on Mordecai's side.
- The Lunch Club: after he ruins Mr. Maellard's lunch, he and Benson have to write Meallard a letter. They have fun instead and Benson and Rigby leave Maellard an insulting note with both of them deciding to resign.