Rough plan for the Alien Races:
Grey Aliens, divided into Alpha and Beta castes. Betas are the short squalid types. They are actually the child soldiers of the Greys. Betas possess a more than human level of cruelty, cunning and tenacity. They are immoral but intelligent, have keen senses, physical and extra-physical. While not physically devloped, they are dangerous at all ranges with ranged weapons. Alpha Greys stand at 1.8 to 2 meters tall, and are as physically potent as any well-trained human soldier. Most are well versed in close-combat martial arts on top of their weapon skills. When not leading squads of betas, some Alpha Greys may form specialized commando units. They have somewhat more balanced personalities and tactics than unled Betas, but are no less bloodthirsty.
There are some Masons who believe that the Greys are devolved inner-terrestrial Lemurians. And that reincarnating black magicians sometimes take that form while waiting for their souls to disintegrate.
Reptilian Race: Commanded by sentient lizard men. They may employ genetically modified velociraptors as bloodhounds, and large carnivorous dinos as shock troops. Dragons and drakes are also among their ranks. The lizard men themselves can take to the field with plasma/energy weapons.
Primates: An extremely versatile Planet of the Apes army. Chimpanzee type light infantry, Gorilla shock troops. In co-masonic lore, apes devolved from sexual experiments with humans, rather than humans having evolved from apes.
Necronom IV, the original xenomorph, with all its sexual undertones. It also avoids the laws of ninjitsu that afflicted its movie brethren.
If all goes well, we could throw in a robotic army into the mix... like if Skynet and the Daleks had a baby...
Outline for mission 1: Understrengthed squad of Greys raising hell at a Kindergarten. Craft damaged and somewhat contained by small town mob and local law. Children and any beautiful busty blond young teachers taken hostage and used as human shields. Alien Removal Militia to swoop in and take control hof the situation, in what will either be a Turkey Shoot, or PR fiasco.