Star Teens: Power Hour

Occasionally during Star Girls Unite, several characters from Warner Bros. shows have appeared as guest stars during crossover episodes.

Ben 10: Ultimate Alien

 * Ben Tennyson
 * Gwen Tennyson
 * Sunny Tennyson
 * Julie Yamamoto
 * Ship
 * Charmcaster
 * Darkstar/Michael Morningstar

Batman

 * Batman/Bruce Wayne
 * Robin/Tim Drake
 * Batgirl/Barbara Gordon
 * Alfred Pennyworth
 * Commissioner James Gordon
 * Detective Harvey Bullock
 * The Joker
 * Harley Quinn
 * The Riddler
 * Poison Ivy
 * The Mad Hatter
 * The Penguin
 * Ra's al Ghul
 * Talia al Ghul

Scooby-Doo

 * Scooby Doo
 * Shaggy Rogers
 * Scrappy Doo
 * Daphne Blake

Justice League

 * Supergirl/Kara Zor-El
 * Hawkgirl/Shayera Hol
 * Wonder Woman/Diana Prince
 * Brainiac

Superman: The Animated Series

 * Superman/Clark Kent
 * Lois Lane
 * Jimmy Olsen
 * Lex Luthor
 * Mercy Graves

The Real Adventures of Jonny Quest

 * Jonny Quest
 * Jessie Bannon
 * Bandit
 * Dr. Quest
 * Race Bannon
 * Estella Valesquez (Jessie's mother

Teen Titans

 * Robin
 * Cyborg
 * Raven
 * Beast Boy
 * Starfire
 * H.I.V.E
 * Terra
 * Slade

Generator Rex

 * Rex Salazar
 * Agent Six
 * Bobo Haha
 * Dr. Rebecca Holiday
 * Noah Nixon

The Secret Saturdays

 * Zak Saturday
 * Doc Saturday
 * Drew Saturday
 * Fiskerton
 * Komodo
 * Zon
 * Doyle Blackwell