Massively multiplayer online real-time strategy game (MMORTS) mixes the genres of real-time strategy and Massively multiplayer online games, possibly in the form of web browser-based games, in which a very large number of players interact with one another within a virtual world. Players often assume the role of a general, king, or other type of figurehead leading an army into battle while maintaining the resources needed for such warfare. The titles are often based in a sci-fi or fantasy universe and are distinguished from single or small-scale multiplayer RTSes by the number of players and common use of a persistent world, generally hosted by the game's publisher, which continues to evolve even when the player is offline.