The story of Rebellion starts where the Vengeance one ended. You have won the battle over Gargantua but this last one had leave you in such a shape that even your mother would not recognize you. You have lost all of your weapons during the battle and you're are severely wounded. Nevertheless, some scientists who kept themselves away during your last fight are coming to give you first aid... They don't have the time to help you. A marines platoon arriving begins to shoot them down and one of the grunts puts a highly explosive satchel charge a few meters from you that cause the ground to collapse when exploding.
This mod has some ugly bugs, and very dark sometimes, but it's still very interesting ;P