An expansion pack, expansion set, supplement, or simply expansion, is an addition to an existing role-playing game, tabletop game, video game, collectible card game or miniature wargame. These add-ons usually add new game areas, weapons, objects, characters, adventures or an extended storyline to an already-released game.[1]
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, it may choose to develop the expansion itself, or it may do both.
Board games and tabletop RPGs may have been marketing expansions since the 1970s, and video games have been releasing expansion packs since the 1980s, early examples being the Dragon Slayer games Xanadu Scenario II[2] and Sorcerian.[3] Other terms for the concept are module and, in certain games' marketing, adventure.[citation needed]