|The following is based on Fallout Tactics and some details might contradict canon.|
Gravestone is a location within Kansas City in Fallout Tactics, which can be reached from Bunker Gamma. It is a small ghoul town belonging to Kansas City and created into its center, located in western Missouri. The rest of the city belongs to Gammorin's Army.
The ghoul survivors of Kansas City after the Great War formed a town in the center of the ruined city, now renamed Gravestone. Before 2197, the ghouls began to form a peaceful community and a cult, worshiping the only nuclear bomb left intact in the silo, which they called "Plutonius". T-Minus became the first leader and bishop of Gravestone, in charge of both religious and civil affairs. Around 2198, Gammorin's Army established a base in Kansas City, and tried to assault Gravestone in order to get the atomic bomb worshiped by the ghouls. The ghouls hid in the cathedral, where "Plutonius" was held. A few weeks later, Defcon the actual leader and bishop of Gravestone, asked the Midwestern Brotherhood of Steel to help protect them against Gammorin's Army.
The Midwestern Brotherhood of Steel eventually came to help, with armed ghouls and acolytes of the cathedral; they killed most of the attacking mutants. The squad was commanded by the Warrior, who managed not only to protect the place, but also launched a retaliation attack on the super mutant base in Kansas City, killing their three commanders in the process and securing the area. In exchange for their aid, the Midwestern Brotherhood of Steel demanded the ghouls to give them "Plutonius", which was later used to blast open the vault door of Vault 0.
The mission includes the entire city of Kansas City and not only Gravestone. It involves defending the ghoul town from an impending super mutant invasion while simultaneously finding and eliminating Gammorin's Army commanders.
Gravestone appears only in Fallout Tactics.