An expansion pack, expansion set, supplement, or simply expansion is an addition to an existing role-playing game, tabletop game or video game. These add-ons usually add new game areas, weapons, objects, characters and/or an extended storyline to complete an already released game. While board game expansions are typically designed by the original creator, video game developers sometimes contract out development of the expansion pack to a third-party company, (see Hellfire for Diablo), it may choose to develop the expansion itself or it may do both (Ensemble Studios developed the real-time strategy game Age of Empires III and the first expansion called the WarChiefs itself, but contracted Big Huge Games for the second expansion pack, the Asian Dynasties). Board games and tabletop RPGs may h