Shinji is forced to fight an infected Evangelion Unit-03 and watches its pilot, his friend and classmate Toji Suzuhara, incapacitated and presumably permanently crippled. Asuka loses her self-confidence following a defeat and spirals into depression. This is worsened by her next fight, against an Angel which attacks her mind and forces her to relive her worst fears and hidden insecurities, resulting in a mental breakdown. In the next battle, Rei self-destructs Unit-00 and dies to save Shinji's life. Misato and Shinji visit the hospital where they find Rei alive but claiming she is "the third Rei". Misato forces scientist Ritsuko Akagi to reveal the dark secrets of Nerv, the Evangelion boneyard and the dummy plug system which operates using clones of Rei. This succession of events leaves Shinji emotionally scarred and alienated from the rest of the characters. Kaworu Nagisa replaces the catatonic Asuka as pilot of Unit-02. Kaworu, who initially befriends Shinji and gains his trust and affection, is in truth the final foretold Angel, Tabris. Kaworu fights Shinji, then realizes that he must die if humanity is to thrive and asks Shinji to kill him. Shinji hesitates but eventually kills him. He is overcome with guilt.