A raid is a type of mission in a video game in which a number of people attempt to defeat another number of people at a player-vs-player or a number of NPCs in a player-vs-environment battlefield. The term raid itself stems from the military definition of a sudden attack and/or seizure of some objective. This type of objective is most common in MMORPGs, and usually but not necessarily occurs within an Instance dungeon. In RTS games like StarCraft, the term is used differently; see Raid (military).