You and another player go against each other, with a simple goal of earning more points than the other within a time limit. Both factions have the same type of units with the same total amount of each, although it may change depending on which players control certain facilities that help reinforce them.
Units = The infantry, vehicles, and so on.
Time = The amount of time for you to gain more points then your opponent.
Points = What you gain by destroing enemy units.
Bonus Points = Both "First Strike" and "Player Bonus". "First Strike" gives you 25 extra points for being the first one to make a kill. "Player Bonus" gives you 10 extra points for eliminating an opponent controled unit.
Capture Points = Facilities that you capture give you 100 point along with reinforcing you with new units. If you capture two of the same types, your respawn time of that facility is cut in half.
Respawn Points = Spots where units come from (Infantry from HQ/Barracks, Air units from Airports, ect.).