Before anything, lets be clear on who exactly it is were talking about here. Not the pouting, whining, underling of Krang cartoon/Archie universe Shredder, nor the psychotic "What did he use, a flower? Hahahah!" live-action Shredder from the movies and new TV series. Neither were meant to be taken seriously, and lets face itthey werent.
The only incarnation of Shredder that could truly be considered definitive is the comic book character, the direct brainchild of Kevin Eastman and Peter Laird who debuted along with the Turtles in the very first issue of the Mirage series. He was depicted not as a doting world-domination-and-doing-evil villain (a silly modus operandi the cartoon would repeatedly beat us over the head with, to give Saki no merit), but the intelligent, tactful leader of the New York Foot Clan and martial arts master. In essence, an organized crimelord. Owing nearly all of his life to vengeance against Hamato Yoshi, the murderer of his older brother, Oroku Nagi, the Shredder persona was born. The Shredder has been called evil on occasion, and even "evil incarnate," but that is open to debate.
Oroku Saki was the leader of the New York Foot Clan and the younger brother of Oroku Nagi. When Nagi was slain at the hands of Hamato Yoshi, 7 year old Saki made a vow of vengeance. Joining the Foot Clan, Saki rose up the ranks quickly, impressing those in power so much that they gave him the assignment of starting a new branch of the Foot in New York at 18. Successfully building the branch in less than a year, Saki created his "The Shredder" persona, then directing his attention to matters of revenge. Tracking Hamato Yoshi and Tang Shen to their apartment, Saki broke in and slew them both. His vow of vengeance then fulfilled, Saki and his Foot Clan had a relatively uneventful fifteen years, though during which time he became involved with the female assassin Headhunter, who is possibly the mother of his daughter, Pimiko. For reasons unknown, the mother of his daughter left Saki, seeking the protection of Go-Komodo (Big Bang Comics #10, TMNT Vol. 3, #5). Suddenly Saki became confronted with an offer of honorable combat from Splinter, the pet rat of the deceased Hamato Yoshi. Saki met the Turtles and, in a fierce rooftop duel, was killed when the thermite grenade he was preparing to use against them was hurled along with him when he was thrown off the roof by Donatello, exploding beside him (TMNT Vol. 1, #1).
For nearly three years the Foot Clan worked towards resurrecting their fallen master. Finally, with the combined resources of the Foots technology and scientific knowledge, an answer was found within a unique form of cloning. Worms, genetically altered, could feed off a persons remains, come together, and eventually reform as the person whose remains they ingested. Three test subjects of Saki were created before they had the entire technique done on his charred, blasted remains. It was successful (TMNT Vol. 1, #20 & 21). Saki made his resurrection known to the Turtles when he had the Foot lure Leonardo into his trap, fighting and beating the Turtle within an inch of his life, then throwing him through the window of the Turtles home in April ONeils "Second Time Around" store. The Turtles, with the help of Casey Jones, managed to fight off the Foot, though not before they started the fires that would burn the entire store to the ground. Leaving Shredder and the Foot behind, the Turtles went to Caseys deceased grandmothers estate in Northampton to heal and contemplate (Leonardo special, TMNT Vol. 1, #10).
Raphael, fed up with his brothers lack of action, returned to New York to fight Saki. Instead, he found Zog, a Triceraton he quickly befriended to his cause of finding the Shredders lair. Rejoining with the other Turtles, they invaded Sakis Hudson Block headquarters, fighting their way through countless Foot Soldiers, Shredder Elite Foot, and the three test subjects of Saki, Leonardo alone found and confronted Saki. In an intense katana sword duel, Saki was beheaded by his opponent. His remains were sent burning on a raft into the New York harbor (TMNT Vol. 1, #19 - 21).
Several years later, Raphael, after witnessing the gunning down of the entire ruling council of the New York Foot by the hitmen of mobster Antoine Puzorelli, stumbled into the chamber where Saki had once forged his armor. Donning one of the suits of Sakis armor he found, Raphael began his masquerade as the Shredder. When approached by surviving members of the Foot and challenged by one of them, he slew his challenger and asserted command of the entire New York Foot, usurping Karai, whose whereabouts remained unknown. Invading Antoine Puzorelli's villa in New York's west end, Raphael forced a pact of peace with Puzorellis syndicate. His brothers later discovered his identity by infiltrating his headquarters by disguising themselves as his Elite Foot, though they only laughed about it (TMNT Vol. 3, #13 - 16). Later Pimiko, found the remnants of her father's Shredder Elite, who accepted her as the rightful heir to the mantle of the Shredder, not Raphael. She ordered the Elite to "keep them in sight," wanting full reports on everything the Turtles did and everywhere they went (TMNT Vol. 3, #18). Later, Pimiko attempted to assassinate Splinter in April O'Neil and Casey Jones' apartment. She failed, and was subdued and bound by Splinter. When having tea with Splinter and Casey, she made her escape. Soon afterward, with the impartial support of two members of the Japan Foot Clan's Ruling Council of Five, she appeared before Raphael with her loyal Shredder Elite, proclaiming her birthright as the heir to the mantle of the Shredder in a challenge to Raphael (TMNT Vol. 3, #20 & 21). After Raphael refused to kill Pimiko after besting her, he was shunned by the Ruling Council members. A woman in bladed armor steps forth to combat both Pimiko and Raphael - Lady Shredder, a woman of as-yet unknown identity (though presumed to be one and the same with Karai) (TMNT Vol. 3, #22 & 23), a woman covered in metal, a match for magnets and magnet enthusiasts everywhere.
The story is left thus...
SHREDDER TIMELINE
25 years ago. . .
In the Japanese Foot Clan, Oroku Nagi and Hamato Yoshi competed over the love of a woman, Tang Shen. Nagi, in frustration, attempted to kill Shen before Yoshi, seeing what was about to happen, fought and slew Nagi before he could do the deed. Yoshi was banished from Japan, exiled to New York with his wife.19 years ago. . .
Oroku Saki, the younger brother of Nagi who had long since vowed vengeance against the murderer of his kin, became the Shredder and led the New York Foot Clan. He sought out and killed both Tang Shen and Hamato Yoshi.5 years ago. . .
The Shredder first encountered the Teenage Mutant Ninja Turtles, the students of the rat that had once been Hamato Yoshis pet. A battle of vengeance and honor ensued. The Shredder was horribly lacerated, then blown apart when a thermite grenade he intended to use on his enemies went off in his hands as he was thrown from a rooftop.
[ AS CHRONICLED IN TMNT VOLUME 1, #1 ]2 years ago. . .
The New York Foot Clan used an experimental technique involving a collective of earthworms that fed off the remains of Shredder and cloned him. With his memory fully intact, he continued his work. The Ninja Turtles sought him out and again a battle was fought, this time with Leonardo alone. They sword-fought fiercely and traded many blows before Shredder became decapitated. The New York Foot Clan fell into disarray and chaos following the death of their leader.
[ AS CHRONICLED IN TMNT VOLUME 1, #19, 20, AND 21 ("RETURN TO NEW YORK") ]1 year ago. . .
The New York Foot Clan was restored as its new leader, a female ninja named Karai, arrived from Japan and quelled its inner turmoil through a pact with the Turtles that eliminated the Shredders most trusted warriors, the Elite Foot.
[ AS CHRONICLED IN TMNT VOLUME 1, #50-62 ("CITY AT WAR") ]Present Day. . .
The Teenage Mutant Ninja Turtles enter dark times as they battle the forces of Warlord Komodo, the daughter of Shredder, Pimiko, and a Triceraton invasion. The Turtles have all but forgotten about their former arch-nemesis as they suffer through a series of terrible casualties. Meanwhile, Raphael assumes the role of the Shredder, a role that becomes contested by Pimiko and her then-loyal Shredder Elite, as he dons the armor of Oroku Saki and assumes control of the New York Foot until the enigmatic "Lady Shredder" steps forth to contest both Pimiko and Raphael's claim.
[ AS CHRONICLED IN TMNT VOLUME 3, (Image Series) #1-23 ]