Krang is an extraterrestrial from Dimension X. He appears at Teenage Mutant Ninja Turtles.
Fred Wolf Cartoon
Krang is a warlord from Dimension X. Banished from his home, he ends up on Earth where he teams up with Shredder.
As the early Archie Comics issues adapt Fred Wolf Cartoon episodes, his Archie origin is similair, being a warlord from Dimension X who after being banished to Earth teams up with Shredder.
However, this incarnation is also seen destroying all lifeforms on entire planets across Dimension X, when searching for the Turnstone. Krang is later banished by Cherubae to the toxic planet of Morbus. He briefly returns to Earth, in an attempt to take revenge on the Ninja Turtles and Shredder, but is defeated and returned back to Morbus by Bebop and Rocksteady.
Platinum Dunes Films
Krang also appears in Out of the Shadows from 2016. He teams up with Shredder, and arrives to Earth in his Technodrome.
Original Konami Video Games
In the Original Konami Video Games, Krang appears as a boss at many levels.