Sandra and Clara were the wife and child of the soldier Heidern. When Rugal heard of his capabilities, he invaded a top-secret military base and murdered Sandra and Clara in front of Heidern. Heidern, who lost an eye in the attack, created the Ikari Warriors and wanted revenge. It's partially speculated that Sandra and Clara are responsible for Heidern's survival. This is seen in Tatsuya Shinjyouji's KOF '94 manga: Heidern has a nightmare about how Rugal was about to finish him off, but both Sandra and Clara willingly threw themselves in front of him and took the fatal blow instead.