Fallout 3: the Pitt and Operation Anchorage (Add On)

The Pitt
The Pitt allows you to travel to the post-apocalyptic remains of Pittsburgh, Pennsylvania and become embroiled in a conflict between slaves and their Raider masters. Explore a sprawling settlement ravaged by time, neglect, nuclear radiation, and moral degradation. The Pitt is filled with morally grey choices, shady NPCs, new enemies, new weapons, and much more.

Operation: Anchorage
Enter a military simulation and fight in one of the greatest battles of the Fallout universe - the liberation of Anchorage, Alaska from its Chinese Communist invaders. Gain access to unique armour, weapons, and exotic gadgets while you build and command interactive Strike Teams to win the battle and defeat the Chinese base.