Ultimate Battlefront: The Clone Wars is a large mod which adds a custom era (UB:TCW) to most shipped maps as well as to five included custom maps. The mod's biggest feature is the random units; each time upon starting a match, clone legions, heroes, and other units are selected by random. This essentially makes no two games the same, and forces the player to adapt based on the units available. The random feature is sadly single player only, however. The mod can still be played in multiplayer, but the units are preset.
Note: You need the unofficial v1.3 patch installed to play this mod. Starwarsbattlefront.filefront.com