Since man has colonised some of the galaxy, they have discovered many alien races. Considered hostile, they instantly declare war. However, there is another threat lurking, a race of synthetics that only exists to destroy all life, but not even they are the true threat, for another more ancient, darker race is returning.
This is the Legion 'Swarmer' Frigate that is used to Transport Squadrons of Fighters and deploy them in the field. I've gone pretty out there with this design, since the Legion would have quite distinguishable ships.