Crossfire is a fast-paced survivor map (listed as a space race map in OP2). The map contains four allied human players and a hostile AI player. The AI player tries to destroy the human players while the human players try to escape the blight and launch a complete starship.
There are many features in this map that will seem strange to people who have never played a survivor map before. The most important thing to remember in Crossfire is that all of the mines are hidden. You must use a scout to find the mining beacons before you can survey them. You also need to remember to evacuate food in cargo trucks and enough evacuation transports for your colonists. If all of your agridomes are destroyed, your food storage is set to the total food stored in cargo trucks. This ammount then becomes your food storages and falls untill you starve or build a new agridome. Evacuation transports are needed to hold colonists if all of your buildings are destroyed; each transport holds 25 people. Colonists are loaded into transports in this order: Scientists, Workers, Children.
There are a few 'hidden' features in Crossfire too. You'll have to find them on your own.