Repulsor cannon

Repulsor cannons are the main defensive armament of the protoss mothership core. After drawing power from the mothership core's khaydarin crystal core, the repulsor cannon projects a concentrated blast of semi-solid psionic energy—too dense for aerial combat—that causes damage by delivering kinetic and thermal energy. Each shot pierces matter violently, leaving a misty cloud of psionic fire in its wake.