Left 4 Quake is a game that allows the player to make the site a bit more fun and to promote more activity. You will have to install a point, cash system into the site called RibCash.
That is the link to download the game. Although there is no much information about this game for now. But you can download the game and check it out yourself. Yes, you will need to extract the game after downloading and then play it using your emulator.