Every year they all do group Halloween costumes. Here's a few they've done, and what roles they played. Also, the actual costume looks are a lot more suited for the characters, like Holiday's for The Nightmare Before Christmas is DEF glowed up by a lot.
Parks and Recreation:
Holiday- Donna Meagle
Cam- April Ludgate
Birdie- Ann Perkins
Badger- Ron Swanson
Cyrus- Jean-Ralphio Saperstien
Magnus- Andy Dwyer
Adam- Tom Haverford
Casey- Mona-Lisa Saperstien
Brynleigh- Leslie Knope
Gravity Falls:
Holiday- Mabel Pines
Cam- Soos Ramirez
Birdie- Wendy Corduroy
Badger- Ford Pines
Cyrus- Dipper Pines
Magnus- Bill Cypher
Adam- Stan Pines
Casey- Pacifica Northwest
Brynleigh- Grenda
The Nightmare Before Christmas:
Holiday- Dr. Finklestien
Cam- The Sea Monster Lady (you know who I'm talking about)
Birdie- Lock
Badger- Barrel
Cyrus- Sally
Magnus- Jack Skellington
Adam- Mayor
Casey- Oogie Boogie
Brynleigh- Shock
Wednesday characters:
Holiday- Bianca Barclay
Cam- Ajax Petropolus
Birdie- Yoko Tanaka
Badger- Xavier Thorpe
Cyrus- Wednesday Addams
Magnus- Enid Sinclair
Adam- Tyler Galpin
Casey- Rowan Laslow
Brynleigh- Marilyn Thornhill
The Office:
Holiday- Pam Beesly
Cam- Jim Halpert
Birdie- Kelly Kapoor
Badger- Micheal Scott
Cyrus- Dwight Schrute
Magnus- Andy Bernard
Adam- Ryan Howard
Casey- Angela Martin
Brynleigh- Nellie Bertram
And that's only a few! Let me know if you want more.

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