Countdown Vampires

Detective Keith J. Snyder had a problem which involved his previous partner, Wesley Simmons, so he was assigned, as a disciplinary measure, to be a bodyguard for several VIPs who were key to the inauguration of a new horror-themed casino, the Desert Moon. The problems began when a fire broke out and a mysterious black liquid started to pour out of the fire sprinklers, turning the vast majority of the people into vampires that proceeded to devour the remaining survivors. (wiki)