This achievement actually unlocks before you fight the boss, so it's really unlocked for going through the Shadow Broker's ship. Use the electrically pylons to your advantage when outside the ship, so you can stun your enimies, then finish them off. Using biotics outside the ship when the enemie's shield are down can knock them right off the ship, funny AND painful. Take cover in the ship, and use the narrow hallways to your advantage, inside is more of a close quater battle. When you find the drell you're almost there.