Serious Sam 2 is a first-person shooter video game released for Microsoft Windows and Xbox and the sequel to the 2001 video game Serious Sam. It was developed by Croteam and was released on 11 October 2005. The game was initially published by 2K Games, a Take-Two Interactive subsidiary. The game was later made available on Steam on 31 January 2012. While the game was originally released only for Microsoft Windows and Xbox, an unofficial Linux version of the game was created and is being handled by Linux Installers for Linux Gamers. In the single-player campaign, the player assumes the role of hero Sam "Serious" Stone in his adventures against the forces of the extraterrestrial overlord, "Mental", who seeks to destroy humanity. Taking place after the events of Serious Sam: The Second Encounter, Sam travels through various worlds collecting parts of a medallion in an effort to defeat Mental. He is guided by the Sirian Great Council and receives sporadic aid from the natives of the worlds he visits. The multiplayer mode includes online co-op and deathmatch, the latter having been introduced in a patch. Croteam simultaneously developed Serious Engine 2, the successor to their previous game engine, Serious Engine, for use in the game, and the engine is capable of many features of other advanced game engines of the time including high dynamic range rendering and light bloom. The engine supports integration with both Xfire and GameSpy Arcade for multiplayer match finding. Serious Sam 2 is the only game to use the proprietary engine, though the Serious Engine 2 is available for licensing. Gameplay Serious Sam 2'''s gameplay consists almost entirely of the player attempting to defeat dozens of enemies at a time, and thus is relatively simple. The game's story establishes the reasons and methods for how the player travels from chapter to chapter. This is a significant change from the previous games in the series in which the story existed merely to transport the player from place to place in order to kill as many enemies as possible in the process, with the plot consisting merely of messages that the player could disregard without consequence. Serious Sam 2 features the story more prominently, but still maintains the focus on killing as many enemies as possible. The story is developed through the use of cut scenes, which are interspersed throughout the game, especially at the beginning and end