4. Left 4 Liberty
https://www.youtube.com/watch?v=Sgga5POoWLI With the assortment of crazed gunmen and vicious mobsters that populate the world of Grand Theft Auto, one can imagine that walking the streets of Liberty City calls for one eye over the shoulder and a very big gun. Throw ravenous zombies into the mix and you've got an unholy combination that'll make Daryl Dixon soil his pants in bowels-loosening fear. With the Left 4 Liberty mod, hordes of the shuffling undead run amok in the streets of Liberty City giving players the opportunity to play out every little apocalyptic contingency they've ever planned while sitting in traffic (we've all got one). Contamination rate is tracked via the 'infection' meter displayed on the HUD, with every hit causing the rate of contamination to rise while car fuel is tracked with a corresponding meter, meaning that players are encouraged to conserve gas or else risk a long trek through the streets and back alleys of Liberty City. It's a survivalist's paradise.