Metal Gear Solid 4: Guns of the Patriots
In the E3 2006 trailer for Metal Gear Solid 4: Guns of the Patriots, Raiden appears wearing a Tokugawa Heavy Industries exoskeleton and fights several GEKKO Metal Gears armed only with his high-frequency blade (Possibly the same one Olga gave him in MGS2). According to lead character designer Yoji Shinkawa, Raiden is "falling apart" due to a traumatic experience that is yet unknown. He has had most of his body parts replaced by cybernetic prosthetics; the only parts of his original human body which remain are his head and spine. The lower half of his face appears to be synthetic tissue grafted onto bone. He also appears extremely pale - due, according to Hideo Kojima, to the fact he now has white artificial blood. Despite the dramatic physical changes he has undergone, he appears to have retained his memories of his previous experiences with Snake in the Big Shell incident, and tells Solid Snake in the trailer, "It's my turn to protect you."
The trailer shown at E3 2007 shows Raiden engaged in one-on-one combat with Vamp, for whom he is now more than a match (in contrast with their first encounter in Metal Gear Solid 2). Raiden's new body endows him with superhuman speed, strength, and agility, and he appears entirely unfazed by wounds or the prospect of injury: towards the end of the fight, when Vamp has him in a choke hold, he runs his katana through his own abdomen in order to kill his opponent. Vamp asks him if he is immortal, to which Raiden responds, "No. I just don't fear death." At the end of the fight, Vamp asks Raiden "Could you be the one to finally finish me?"
Raiden appears in a later trailer being held by Snake as he coughs up (white) blood, presumably following his fight with Vamp.
