Teen Titans/Teenage Mutant Ninja Turtles: World's Finest

Teen Titans meets Teenage Mutant Ninja Turtles is an American television film produced by Cartoon Network and Mirage Studios.

From Teen Titans:

 * Beast Boy
 * Cyborg
 * Raven
 * Red X
 * Robin
 * Robot Commandos
 * Slade
 * Starfire

From Teenage Mutant Ninja Turtles:

 * Agent Bishop
 * Casey Jones (mentioned)
 * Donatello
 * Foot Soldiers
 * Hamato Yoshi (seen in flashback)
 * Hun
 * Leatherhead (mentioned)
 * Leonardo
 * Michelangelo
 * Purple Dragons
 * Raphael
 * Shredder
 * Splinter