SA-X

When Samus fist encounters the X parasites, they infect her power suit, which forces her to use the Fusion Suit. The X parasites would later take a semi-sentient form in the suit, and would use it to hunt Samus. It would later be known that the SA-X was created to stop the Metroid breeding progam on the space station, with the use of Samus' Ice Beam.