The anti-starfighter missile system referred to as the MS-15 diamond boron missile was created by Sienar Fleet Systems during the Galactic Civil War's peak. The Galactic Empire was its main user.
The MS-15, a product of Sienar fleet Systems, was made up of a streamlined warhead that was one-meter long and could be launched from any concussion missile launcher. Extendable dorsal and ventral flanges on the warhead offered extra protection and maneuverability in the atmosphere, and its armored diamond boron blast plates expanded as they got closer to the target. This made the missile nearly impenetrable to starfighter laser cannons. The MS-15 was faster than even the proton torpedo and had a maximum flight duration of ten minutes.
These missiles could be pre-programmed with specific coordinates to follow, or they could be set to detonate when the internal sensor suite detected a particular quantity of enemy ships, typically three. Although gunners had the option of remotely guiding the missiles, this method carried the risk of enemy jamming devices intercepting them. Furthermore, if friendly ships were within range at the time of detonation, the fifty-meter blast radius may present a hazard.
Around the Battle of Hoth, the Galactic Empire started deploying diamond boron missiles. The MS-15 missiles were carried aboard the freighter Suprosa, which was transporting the second Death Star's readouts, and one was fired after Luke Skywalker attacked the ship. Dash Rendar was unable to destroy the missile before it exploded in the middle of Blue Squadron's fighter formation, killing all eight Bothan pilots and destroying four Y-wings. The Alliance only discovered that the warhead was a diamond boron missile following Rendar's supposed death over Coruscant, and that Dash's inability to destroy it was not his fault.
Despite never achieving widespread adoption, Sienar Fleet Systems went on producing diamond boron missiles, partially as a result of their exorbitant cost of approximately twenty thousand credits apiece. The lack of popularity was also influenced by incidents in which faulty warheads exploded while in storage. Sienar continued to produce diamond boron missiles in limited quantities while attempting to create new, affordable designs.