Command & Conquer is a RTS game, with different universes.
The Tiberium universe is about two factions, GDI and NOD, which are fighting over a material called Tiberium. GDI represents the Earth forces and NOD is a terrorist and fanatic faction.
The Generals universe is setting three factions, inspired by our world: the high-tech US force, the swarming Chinese war machine, or the resourceful Global Liberation Army.
The Red Alert universe is about an alternate history, where Einstein went back in time and killed Hitler. The result is that the Allied and the Soviets are fighting against each others. The last Red Alert introducted a new twist in time: Russians went back in time but by doing so, they allowed a new faction to rise, making it three general armies: Allieds, Soviets and now the Japanese, much know here as the Empire of Rising Sun.
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