The game begins a few years after the second explosion. The radiation released by this incident mutated the plants, animals, and humans in the area. 'S.T.A.L.K.E.R.' is a first-person shooter game that takes place in an alternate reality in which a second nuclear disaster at Chernobyl took place 20 years after the first. 'S.T.A.L.K.E.R.: Shadow of Chernobyl,' released by THQ in 2007, is one such game. By providing gamers the chance to craft their own destinies, they give new meaning to the term 'alternate reality.' Games that take place outside accepted history provide even more fodder for the imagination. Video games continuously stimulate the imaginations of their players.