"TMNT: The Next Mutation" was a concept for fourth live-action movie should this third movie prove a success. In this concept the Ooze that transformed the Turtles and Splinter was still in their bodies causing a much more drastic 2nd mutation. Michelangelo's mutation would have given him a more human appearance allowing him to walk among the people of the City. Donatello's mutation would have given him psychic abilities, but have him wear an optic device because his mutation would cause his vision to deteriorate. Raphael's rage would cause him to mutate into a fearsome creature with claws and spikes jutting from his body. Leonardo would have the ability to mutate his skin into different textures. Splinter would transform into a creature twice his size that he would have limited control over. However, the third movie was not as successful as hoped and the fourth movie was nixed. Concept art for the never made 4th movie can be found as unlockable bonus content in Teenage Mutant Ninja Turtles: Smash-Up (2009). The concept of having the Turtles mutate into creatures was later used in the 'New Mutation' saga of the Teenage Mutant Ninja Turtles (1987) cartoon. Later the "Next Mutation" name was used in Saban's live-action series, Saban's Ninja Turtles: The Next Mutation (1997). Matt Hill, who voices Raphael, is the only actor from the films to reprise his role in the "Next Mutation" series.
