Use a team that inculdes Jean Grey and Carnage (bonus downloadable content required). As Grey, continuously use her "Pyrokine Blast" by pressing R2 + Square and evading. This will quickly fill up your fusion meter while avoiding damage. Once your fusion meter is full, perform a "targeted" fusion with Grey and Carnage. This fusion attacks one target twice, and can even damage or knock out another Boss nearby, while getting health pickups for successful attacks. Repeat the process until the mission clears. If done well, you can unlock Carnage's alternate costume and unlock two trophies specific to this mission with relative ease.