The first DLC Pack for Dragon Ball: Xenoverse is out early on Steam. In order to get the first DLC pack early, you will have to purchase the $25 season pass. The pack comes with a GT Prequel Saga, more Parallel Missions and three characters which include GT Goku, GT Trunks, Pan.
Dragon Ball: Xenoverse DLC Pack 1 comes with two more masters and a few attacks for your created characters as well. You can purchase the DLC pack here.