OK K.O.! Operation: Birthday Bash

'OK K.O.! Operation: Birthday Bash 'is a 2036 direct-to-video film which is the most spectacular crossover film.

Summary
Enid, Radicles, Mr. Gar, Carol, Dendy, Red Action, A Real Magic Skeleton, and Brandon decide to throw K.O. a suprise party for his birthday.

Plot
When Carol discovers that his son's birthday is today, she goes to the bodega to tell everyone about K.O.'s Birthday. So in order to keep him away from preparing the birthday party, she wants Enid, Radicles, and Dendy to go spend the day with K.O., Mr. Gar in charge of everything, Beardo bakes the birthday cake, Punching Judy does the invitation, Red Action, A Real Magic Skeleton, and Brandon setting up the birthday decorations. At the beach city, Amethyst got the message from Email which is an invitation of K.O.'s birthday party and everyone's inviting it, TBA

Cast

 * Courtenay Taylor as K.O.
 * Ashly Rush as Enid, Mrs. Mummy
 * Ian Jones-Quartey as Radicles, Crinkly Wrinkly, and Darrell
 * Melissa Fahn as Dendy
 * Kate Flannery as Carol
 * David Herman as Mr. Gar, Jethro, Beardo and Brandon
 * Ben Jones as A Real Magic Skeleton
 * Kali Hawk as Red Action
 * Jim Cummings as Lord Boxman
 * Steven Ogg as Professor Venomous
 * Lara Jill Miller as Fink
 * Kari Wahlgren as Shannon and Wonder Woman
 * Robbie Daymond as Raymond
 * Chris Niosi as Ernesto, Nick Army, Pird, and Neil
 * James Urbaniak as Mr. Logic and Joff the Shaolin Monk
 * Melissa Villaseñor as Potato, Punching Judy, Drupe, and Mega Football Baby
 * Cole Sanchez as Colewort
 * Andrés du Bouchet as Joe Cuppa
 * Scott Menville as Robin
 * Tara Strong as Raven and Ben Tennyson
 * Khary Payton as Cyborg
 * Greg Cipes as Beast Boy
 * Hynden Walch as Starfire
 * Kevin Michael Richardson as Trigon and Mr. Gus
 * Idris Elba as Darkseid
 * Patrick Warburton as Superman
 * Troy Baker as Batman
 * James Arnold Taylor Flash
 * Dee Bradley Baker as Aquaman
 * Eric Bauz as Belly Bag
 * Lil Yachty as Green Lantern
 * Nicolas Cage as Gentleman Ghost and Lex Luthor
 * Jim Carrey as The Joker
 * Zach Callison as Steven Universe
 * Estelle as Garnet
 * Michaela Dietz as Amethyst
 * Deedee Magno-Hall as Pearl
 * Shelby Rabara as Peridot
 * Jennifer Paz as Lapis Lazuli
 * Miriam A. Hyma as Bismuth
 * Kimberly Brooks as Jasper
 * Tom Scharpling as Greg Universe
 * David Kaye as Grandpa Max
 * Frank Welker as Scooby Doo and Fred Jones
 * Matthew Lillard as Shaggy Rogers
 * Grey Griffin as Daphne Blake
 * Kate Micucci as Velma Dinkley
 * Tracy Morgan as Captain Caveman
 * Ken Jeong as Dynomutt
 * Kiersey Clemons as Dee Dee Skyes
 * Mark Wahlberg as Blue Falcon
 * Jason Isaacs as Dick Dastardly
 * Demi Lovato as Smurfette
 * Rainn Wilson as Gargamel
 * Mandy Patinkin as Papa Smurf
 * Joe Manganiello as Hefty Smurf
 * Jack McBrayer as Clumsy Smurf
 * Danny Pudi as Brainy Smurf
 * Jake Johnson as Grouchy Smurf
 * Gordon Ramsey as Baker Smurf
 * Tituss Burgess as Vanity Smurf
 * Gabriel Iglesias as Jokey Smurf
 * Jeff Dunham as Farmer Smurf
 * Kelly Asbury as Nosey Smurf
 * Julia Roberts as Smurfwillow
 * Michelle Rodriguez as Smurfstorm
 * Ellie Kemper as Smurfblossom
 * Ariel Winter as Smurflily
 * Meghan Trainor as Smurfmelody
 * Peter Browngardt as Uncle Grandpa
 * Adam DeVine as Pizza Steve
 * Eric Bauza as Belly Bag
 * TBA as Mega Cosmetic Maia/Maia Parker
 * Britt McKillip as Lucy Newton/Icy Charm
 * Kath Soucie as Conor Beckett/Sparking Quake