Prototype K-06-SJ

One of the Prototypes made by Kojima and the ultimate version of Samoa Joe until being reverted back in Season 5.

Season 4
Samoa Joe himself had already beaten Extra during the Mixed Match Challenge, even if his partner had lost.

But something wasn't right, after all this time, all this pain, all this time waiting to take revenge of Extra, just beating him wasn't enough... he wanted him DEAD. So he went to Kojima and asked to be turned into a living murder machine. He also asked for a small favor-- to not use any kind of anesthetic during the operation.

And so, all of Joe was turned into machine sans his upper head, and left arm due to time constraints. His arm was upgraded from a mechanic servo into a full fledged artificial muscle arm, with the added benefit of extensible fingers that turn into claws. The lower portion of his head is a hard to move metal jaw that contains mostly tubes that go into his head. The rest of his body is a hard alloy of Adamansteel and Macacquium.

His eyes and ears are nano upgraded and were scheduled to be further mechanized, but Sminem's sudden appearance forced Kojima to send him as is.

Episode 9
During the Prototype Wars, he was supposed to be sent to The Locker Rooms and attack the wrestlers (That's why the previous match had 3 wrestlers), but he went AWOL and started calling for a match with his opponent. Soon they met for their rivalry to go all-out.

Episode 10
Quickly deployed during the TCR invasion, he locked on a target whose fighting style invoke a very familiar fury in Joe.

Season 5
He got in favor of Hideo thanks to his recklessness in the Death Game, granting him his old body back.