gerald robotnik
The grandfather of Maria Robotnik and Dr. Eggman. A renowned scientist who was widely acknowledged as one of the greatest scientific minds of all time, Gerald was responsible for several groundbreaking creations, such as the Space Colony ARK, the Artificial Chaos, the Chaos Drives, the Biolizard and his greatest creation, Shadow the Hedgehog.
Over fifty years prior to the events of Sonic Adventure 2, Gerald was asked to lead Project Shadow, a medical program for researching immortality, which he accepted in hopes of finding a cure for a fatal illness afflicting Maria. Eventually, Gerald managed to create Shadow the Hedgehog, though not without drastic measures; he was taken into custody by the military when his work was deemed too dangerous. When learning that Maria had been killed by the military, Gerald slipped into madness and spent his last days plotting revenge against humanity.