Star Metal Bullets are a unique form of ammunition, most notably found in Caledonia.
Star Metal Bullets were created in Caledonia, from Star Metal found inside Caledonia's borders. Star Metal bullets are rare, due to the limited quantities that they could be produced. A Star Metal bullet glows due to the star metal inside, making it easy to tell apart from other ammunition types, such as incendiary ammo.
A cache of these bullets were discovered inside Marefort, the bullets were taken by the Crimson Hoof, who killed the town's mayor who stated they were to dangerous and a townspony who tried to intervene.
Besides the kinetic damage these bullets do, the star metal inside is poisonous. The poison causes an afflicted limb to begin rotting due to advanced necrosis. The poison is normally fatal in most cases, with only one known survivor of star metal poisoning, Hired Gun.