Serious Sam 2 (previously Serious Sam II) is a first-person shooter video game released for Microsoft Windows and Xbox and the sequel to the 2002 video game Serious Sam: The Second Encounter. It was developed by Croteam and was released on October 11, 2005. The game was initially published by 2K Games, a Take-Two Interactive subsidiary. The game was later made available on Steam on January 31, 2012.