Alliance are a serie of different mods. On the Star Wars GC, you can play the civil war Empire vs Rebel era + Black Sun and soon the Republic and CIS.
This will be the new Abregrado Rae ground map, it adds several buildings made as you could see on the Trilogy of the New Republic comics. Images.wikia.com Images.wikia.com Other special features from the map will be how even if you can deploy a Walker, it can not cross the water. However the map is not too big and some of these big machines can fire very far but it will set a new type of strategy. Other point will be how you can bombard all the city and destroy all the buildings if you want.
This map as the others will add skirmish versions. After it will make a bigger Fondor map and probably one Myrkr.
Wow...you sir are a artist.