Shadow the Hedgehog

Shadow was created by Professor Gerald Robotnik through genetic engineering. His creation was part of an experiment to cure Gerald's granddaughter, Maria, from a deadly illness. As Maria and Shadow formed a strong bond together, the Guardian Units of Nations (GUN) saw Shadow as a threat, and raided the ARK where Maria and Shadow lived. Maria, before getting killed by GUN, sent Shadow on a escape pod to Earth. Traumatized with the death of his best friend, and a broken promise, Shadow unleashed hell against GUN, killing everyone who took Maria from him.