Quake II released on December 9, 1997, is a first-person shooter computer game developed by id Software and distributed by Activision. It is not a sequel to Quake; it merely uses the name of the former game due to id's difficulties in acquiring a trademark for alternative titles.
The soundtrack for Quake II was mainly provided by Sonic Mayhem, with some additional tracks by Bill Brown.
The next game released by id with the title Quake, Quake III Arena, is also not considered to be related to Quake and Quake II as it is multiplayer focused, and has a dissimilar storyline.
A direct sequel, titled Quake 4, was released in October 2005 for the PC (Microsoft Windows and GNU/Linux), and later for the Xbox 360 and the Apple Macintosh. A prequel to Quake II, Enemy Territory: Quake Wars, has been produced by Splash Damage.
Quake II takes place in a science fiction environment. In the single-player game, the player assumes the role of a Marine named Bitterman taking part in "Operation Alien Overlord", a desperate attempt to protect Earth from alien invasion by launching a counter-attack on the home planet of the hostile cybernetic Strogg civilization. Most of the other soldiers are captured or killed almost as soon as they enter the planet's atmosphere, so it falls upon the player to penetrate the Strogg capital city alone and ultimately to assassinate the Strogg leader, the Makron.
The game is played in general first-person shooter paradigms, in which the player shoots enemies from the perspective of the main character. The gameplay is very similar to that featured in Quake, in terms of movement and controls, although the player has been slowed down, and now has the ability to crouch. The game retained four of the original Quake's weapons (shotgun, super-shotgun, grenade-launcher and rocket launcher), although they were all completely redesigned and made to function in slightly different ways. The remainder of Quake's eight weapons (axe, nail-gun, super-nailgun and Thunderbolt) are gone. Newly introduced weapons are the blaster, machinegun, chaingun, hyperblaster, railgun and BFG10K. Some power-ups from Quake are still present, including quad damage.
Anche grazie al supporto di software esterni come Gamespy e All Seeing Eye, che aiutano ed organizzano la ricerca di server di gioco su Internet, il gioco online è entrato nelle abitudini di molti videogiocatori.
Alcune mappe multiplayer di Quake 2 sono diventate talmente "dei classici" da essere state ricreate per Quake 3 da alcuni mapper appassionati. Nella versione per il Nintendo 64, il multiplayer non è online, ma si gioca al massimo in quattro sulla stessa console. Lo scopo principale è di uccidere più volte possibile gli altri giocatori.