Utrom

This is a list of alien races from Teenage Mutant Ninja Turtles.

The Antarians hate violence and appear in the "Invasion of the Turtle Snatchers" episode of the 1987 cartoon, when a family from a planet orbiting Antares travels to the Earth. The family members are named Klaatu, Barada, & Nikto (a nod to the famous phrase from The Day the Earth Stood Still).

The Federation or The Human Federation is a militant civilization led by humans (aliens that resembled humans in the 2003 animated series) whose galactic empire spans many planets. Despite sharing the same species name and appearance, the Federation's connection with Earth is unknown, as many Federation humans have no knowledge of Earth. in the original Mirage comics and the 2003 animated series they are the arch-foes of the Triceraton Republic under Prime Leader Zanramon, with General Blanque leading them in the conflict. Their attempts to destroy their enemies led them to pursue Professor Honeycutt, a former Federation scientist whose mind was transferred into a robotic body due to an accident. The Federation attempted to exploit Honeycutt's Teleportal invention, but were thwarted by the attempts of the Triceratons to do likewise and the unexpected arrival of the Turtles. They later pursued Honeycutt and the Triceratons to Earth in an effort to capture Honeycutt, only for a virus created by the Professor to render their fleet helpless. Aid from the reorganized Triceraton Republic led to peace between the two factions.

The Kraang are a species of aliens that appear in the 2012 TV series, which are an homage to both Krang and the Utroms. Like the Utroms, they can have human disguises, however, they are all identical. They are one of the main antagonists of the series.

The Kraang's voices are provided by Nolan North, with at least one female Kraangdroid design voiced by Cassandra Peterson. Not unlike the Utroms in the Mirage comics and 2003 TV Series, they are portrayed as a race of brain-shaped aliens from Dimension X that pilot robotic bodies who were responsible for bringing the mutagen that was responsible for the Turtle's mutations to Earth. Their history became intertwined with the Turtles when they caught Splinter spying on them and attacked him while he was holding the not-yet-mutated Turtles, causing them to mutate when one of the Kraang accidentally dropped a mutagen canister on them.

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Wikipedia