In 2004, ' introduced camouflage to the genre. Set in a jungle, the game emphasized infiltration in a natural environment, along with survival aspects such as food capture, healing and close-quarters combat. The following year, the updated version ' added an online multiplayer mode to the game with stealth elements. Another 2004 release was ', based on the "Chronicles of Riddick" series of movies. The game follows the character of Riddick as he attempts to escape from prison. Action and stealth gaming are combined seamlessly by allowing the character to hide, sneak, or fight his way past most situations. The game was critically acclaimed, and was followed with ' in 2009.