The Psycho Mantis are an Alien Species originating from another Dimension. Their largest and most powerful faction, The Supreme Empire, commenced an Alien Invasion on Earth after Humans invented Inter-Dimensional travel before they did. They have various ranks, all of them being shielded. Their lowest rank, Soldiers are the weakest and least skilled among their ranks. Captains serve as Squad Leaders and pilot multi-personal vehicles. Ultras are tough warriors, sometimes wielding explosive weapons. Stealths specialize in sneaking around and gathering information. Spec-Ops are tough warriors who are sent on very hazardous and/or important missions. Heavies specialize in using Heavy Weapons and always use them, they almost take less damage from them.