StarCraft Brood War is the expansion pack for the military science fiction real-time strategy video game StarCraft. it was developed by Blizzard Entertainment. Taking right after the events of StarCraft the Zerg Overmind is dead, and the Zerg swarms over the war torn Protoss world of Aiur have run amok without their leader. Only groups of Protoss and Terran survivors remain on Aiur, mainly consisting of Captain James Raynor, Dark Templar Zeratul, Judicator Aldaris, and the newly elected Praetor Artanis. Without their now fallen leader Tassadar, the Protoss and Terran survivors escape the Zerg to the Dark Templar world of Shakuras where they plan to rebuild their army and commence their strike upon the Zerg race.

Meanwhile, the UED has come to the Koprulu Sector with plans to neutralize the Terran Empire, now ruled by former renegade Arcturus Mengsk and former Confederate General Edmund Duke but they are in for more than they expected. As for the Zerg, Kerrigan, the self-styled Queen of Blades has assimilated the Zerg swarms along with the cerebrate Daggoth as they plan their vengeance against the Protoss and Humans.