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Kevin Eastman got the idea for the Shredder's armor from large trapezoidal cheese graters which he envisioned on a villainous character's arms. He then said, "Could you imagine a character with weapons on his arms like this?" Peter Laird suggested the name The Shredder.

In the original comic books from Mirage Comics, Oroku Saki had an elder brother by the name of Oroku Nagi, who had been killed by fellow ninja Hamato Yoshi (the owner of Splinter, the Turtles' mentor) in a feud over a woman named Tang Shen, resulting in Yoshi fleeing with Shen to the United States.

Angered by the death of his elder brother, Saki joined the Foot Clan and trained to be a ninja. He quickly became one of their deadliest warriors and rose up the ranks and was chosen to lead the Foot's American branch. Operating in New York under the name of The Shredder, Saki used the opportunity to avenge his brother by killing Yoshi and Shen.