Biggs was changed several times.
Initially in the dark days of U-boats, you were forced to shoot him with whatever weapon you had available, even if this meant giving up a better shot (such as a torpedo locked onto another ship, or a weapon without range on Biggs).
Then once the excesses of the triple scouts lists were nerfed, he was changed again to his current version. Now you choose a weapon, then have to shoot Biggs if you can (so torpedoes can ignore Biggs if their TL is on another ship, an ion cannon turret can shoot ignoring Biggs if he's at R3, etc.).