Alpha was a highly-advanced artificial intelligence created almost 50,000,000 years ago by an ancient and super-advanced race of extraterrestrials known as Precursors. Alpha was created for the sole purpose of doing battle with the
and hopefully stopping their genocidal campaign. Originally, Alpha was nearly the size of Luna, but after sustaining heavy damage in it's final bout with the Reaper fleet, it's main core jettisoned from it's body to survive and rocketed itself across the galaxy. Alpha would find itself embedded in the center of a mass of asteroids called Sigma centuries later.
The advanced AI that is Alpha is made up of many programs, similarly to Reapers though many more programs. It is capable of copying multiple programs and beaming them to other VIs or AIs to cause sentience within a machine. Alpha itself is composed of nanotechnology which allows Alpha to assimilate metals like steel and silicon and create materials from them. Alpha can create and manipulated powerful mass effect fields and create kinetic barriers around certain areas as a defense mechanism. Alpha's most prominent ability is it's power to create sentient synthetics whom are so advanced that they are nearly biological in nature.