The Enemy is the Capital Army - S1.E5

The Capital Army unveils a new mobile suit, the Elf Bullock, piloted by the mysterious Mask, who leads a team to once again attack the Megafauna. After having gained the trust of the Megafauna crew, Bellri also promises to Aida that he will protect the ship in order to make up for his killing of Cahill, and once again helps fight off the attacking Capital Army mobile suits. However, Bellri and Noredo reveal that they are secretly spying on the pirates and have a plan to escape with the G-Self.