Moritori Rex is a former Grandmaster of the Dark Legion and grandson of the infamous Dimitri. Moritori Rex found himself becoming a spy for the Dark Legion when he was mistaken for the Guardian Tobor and brought to the Brotherhood of Guardians' secret base Haven. For many years, Moritori Rex managed to pass himself off as Tobor until his true identity was revealed by Knuckles the Echidna. Following this, he rejoined his fellow Dark Legion members and served under Dimitri, who had taken command of the Legion. After the Dingo takeover of Angel Island, Moritori Rex was captured and studied by Dr. Finitevus and tossed into the Twilight Zone along with the rest of the surviving Brotherhood members when the mad scientist had completed his studies.