AliensThe Alien faction is made up of monsters that have allied themselves with the Vortaak invaders and thus their prime goal is to destroy the humans and conquer Earth. Alien monsters are driven by power surges and so attack monsters that destroy Surge (or regular) crystals or Vortaak forces and buildings. They will on the other hand ally themselves with those who preserve crystals or destroy human forces. The Alien monsters are:
MutantsMonsters from the mutant faction are driven by lust for power more than anything else. Because of this they are drawn to crystals and so will destroy all in their path to get such power; monsters, humans and even Vortaak, and so Mutants will ally themselves with others monsters that do just this and attain Critical Mass. They will fight monsters that do not do enough destruction. The Mutant monsters are: