Black Star (Drala Fi' in Minbari) was a Sharlin Class Warcruiser in the fictional science fiction universe of Babylon 5. The Black Star served as one of the flagships of the Minbari Federation fleet, until its destruction in the year 2245. (Some sources give a different class name for the Black Star, referring to it as a "Shargotti" class. This is chiefly because the Black Star was shown to be larger than other Sharlins which it traveled with, and thus may have been a different class. The class of the Black Star has never been stated on screen.)
As told in the episode Points of Departure, during the course of the Earth-Minbari war, on September 30, 2245 the Black Star entered the asteroid belt between Jupiter and Mars. There the Earth Alliance warship Lexington was escorting a number of warships and supply vessels. The far more advanced and powerful Black Star proceeded to quickly destroy and disperse most of the Earth fleet. The Lexington was heavily damaged and crippled in the attack. The ship's commanding officer, Captain Roger Stearns, was killed in the attack when a large metal beam was ripped off the bridge's ceiling and hit him. Commander John Sheridan, the ship's first officer, survived the attack and took command of the Lexington. Knowing that it was only a matter of time before the Black Star found the Lexington, Sheridan devised a strategy that would use the asteroid belt to his advantage. He ordered the belt mined with nuclear weapons, and then transmitted a fake distress signal to lure the ship toward the Lexington. Sheridan knew that it was standard Minbari doctrine to ignore all surrender pleas and destroy all Earth vessels without mercy, regardless of any damage the Earth vessels may have sustained. As the Black Star approached his ship for the kill, Sheridan detonated the nuclear mines attached to nearby asteroids, catching the Minbari ship in the explosions and destroying it.
The Black Star was the most important Minbari cruiser destroyed in the war, and it was the only clear-cut human victory of the war. The Minbari also lost three heavy cruisers in this attack, in addition to the Black Star. It did little to halt the Minbari advance, but it did raise morale in the Earth Alliance and encouraged the humans to keep fighting.
In the decade following the Black Star's destruction, many Minbari - especially within the warrior caste - harbored a strong dislike of Sheridan, and called him the "Starkiller" because he destroyed the Black Star in a sneak attack (which they considered a dishonorable act). Sheridan, on the other hand, never felt any remorse over what he had done; as the ranking officer aboard a warship in a time of war, his duty was to protect his crew and defeat the enemy, and fulfilling that duty meant resorting to asymmetric warfare. The fact that the Minbari had a "no quarter" policy and destroyed any human ship regardless of combat ability/status (something most humans considered dishonorable) was also a strong motivational factor.
When Sheridan took command of the Babylon 5 space station, many Minbari were at first angered by the choice. However, when the Shadow War began, the Minbari put aside their contempt for Sheridan and joined with him to drive the Shadows from the galaxy. Near the end of the Shadow War, Sheridan would once again use the same tactics that he used against the Black Star. He seeded a number of asteroids in the Corianna solar system with nuclear weapons, and used these weapons to attack a number of Vorlon and Shadow vessels.