Teenage Mutant Ninja Turtles Season 1

Ten centuries later, around one day in 198X, Atemu Shredder adopted his adopted daughter Karai in Japan (who happened to be the direct blood descendant of Tengu Schreider Korozaki) and taught her everything about ninjas. Perhaps considering that the development of earth's technology would allow him to return to space, he made Karai his heir and told her all the truth about being an alien. Subsequently, following the news of other escaped Atems on Earth, Artem Shredder moved to the United States, and soon obtained the golden key to the city issued by the mayor of New York. He became the largest bourgeoisie in New York, rich in wealth, and owned the tallest building in the city. He also controlled the dark forces in the entire city. At the same time, Shredder brutally killed Master Ryo Hamato, the guardian in the United States. The so-called guardians are warriors on earth who worship and protect Atem's exiles. Hamato Ryo had asked the Five Dragons Ninja Tribunal, which had conquered Tengu Shredder, several times before to help defeat Atem Shredder. However, the Tribunal stated that they only cared about the sealed Tengu and believed that Shredder was an impostor, so there was no need to know him in general. This situation angered Atem Shredder. Later, due to the betrayal of his friends, Hamato Ryo followed the Atem exiles.