Heroes of Might and Magic III: Armageddon's Blade is the first of two expansion packs for the turn-based strategy game Heroes of Might and Magic III. It was developed by New World Computing for Microsoft Windows and released by the 3DO Company in 1999.
Only one of the six new campaigns available in Armageddon's Blade directly concerns the main storyline. The events of Armageddon's Blade immediately follow the events of Might and Magic VII: For Blood and Honor. As the kingdom of Erathia struggles to rebuild following the Restoration Wars, the Kreegans of Eeofol launch a surprise invasion. Already war-weary, the forces of Queen Catherine are no match for the formidable Kreegan army.
Following the death of the Kreegans' king, Xenofex, a usurper named Lucifer Kreegan takes control of Eeofol and, driven by a vision, begins to seek a means to fashion an ancient weapon known as Armageddon's Blade, capable of setting the world on fire. His general Xeron is tasked with locating the components for the Blade. To stop him, the armies of Erathia and AvLee launch an attack on Eeofol, receiving assistance from the very elements as they manifest in "Conflux" towns. Queen Catherine and the recently liberated King Roland are assisted by the mysterious elven warrior Gelu in the ensuing war. Xeron obtains the Blade, but is defeated by Gelu on his return to Eeofol. Gelu claims the Blade, and, at the behest of Queen Catherine, uses it to slay Lucifer Kreegan. Following this event, the Ironfists return to Enroth and the Blade is passed on to Gelu. The story is continued in Heroes Chronicles: The Sword of Frost, eventually leading to a cataclysm that sets the stage for Heroes of Might and Magic IV.