Due to the Federal Housing Regulations act of 1995 all buildings must be constructed with a "kill brick" which when removed will topple the entire structure. Some of the more state of the art buildings simply have a virtual brick that when activated via electronic pulse dissintegrates causing the formerly stated chain reaction to occur. These measures are set to thwart possible alien attacks and to discourage multiple gangs and organized crime syndicates from taking refuge in the same place at the same time.